diff --git a/src/Common/src/Interop/Unix/System.Native/Interop.Access.cs b/src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.Access.cs
similarity index 100%
rename from src/Common/src/Interop/Unix/System.Native/Interop.Access.cs
rename to src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.Access.cs
diff --git a/src/Common/src/Interop/Unix/System.Native/Interop.ChDir.cs b/src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.ChDir.cs
similarity index 100%
rename from src/Common/src/Interop/Unix/System.Native/Interop.ChDir.cs
rename to src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.ChDir.cs
diff --git a/src/Common/src/Interop/Unix/System.Native/Interop.GetEUid.cs b/src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.GetEUid.cs
similarity index 100%
rename from src/Common/src/Interop/Unix/System.Native/Interop.GetEUid.cs
rename to src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.GetEUid.cs
diff --git a/src/Common/src/Interop/Unix/System.Native/Interop.GetHostName.cs b/src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.GetHostName.cs
similarity index 100%
rename from src/Common/src/Interop/Unix/System.Native/Interop.GetHostName.cs
rename to src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.GetHostName.cs
diff --git a/src/Common/src/Interop/Unix/System.Native/Interop.GetPwUid.cs b/src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.GetPwUid.cs
similarity index 100%
rename from src/Common/src/Interop/Unix/System.Native/Interop.GetPwUid.cs
rename to src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.GetPwUid.cs
diff --git a/src/Common/src/Interop/Unix/System.Native/Interop.GetUnixName.cs b/src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.GetUnixName.cs
similarity index 100%
rename from src/Common/src/Interop/Unix/System.Native/Interop.GetUnixName.cs
rename to src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.GetUnixName.cs
diff --git a/src/Common/src/Interop/Unix/System.Native/Interop.GetUnixRelease.cs b/src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.GetUnixRelease.cs
similarity index 100%
rename from src/Common/src/Interop/Unix/System.Native/Interop.GetUnixRelease.cs
rename to src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.GetUnixRelease.cs
diff --git a/src/Common/src/Interop/Unix/System.Native/Interop.MountPoints.cs b/src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.MountPoints.cs
similarity index 100%
rename from src/Common/src/Interop/Unix/System.Native/Interop.MountPoints.cs
rename to src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.MountPoints.cs
diff --git a/src/Common/src/Interop/Unix/System.Native/Interop.SysConf.cs b/src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.SysConf.cs
similarity index 100%
rename from src/Common/src/Interop/Unix/System.Native/Interop.SysConf.cs
rename to src/Common/src/CoreLib/Interop/Unix/System.Native/Interop.SysConf.cs
diff --git a/src/Common/src/Interop/Windows/advapi32/Interop.LookupAccountNameW.cs b/src/Common/src/CoreLib/Interop/Windows/Advapi32/Interop.LookupAccountNameW.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/advapi32/Interop.LookupAccountNameW.cs
rename to src/Common/src/CoreLib/Interop/Windows/Advapi32/Interop.LookupAccountNameW.cs
diff --git a/src/Common/src/Interop/Windows/Interop.BOOLEAN.cs b/src/Common/src/CoreLib/Interop/Windows/Interop.BOOLEAN.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/Interop.BOOLEAN.cs
rename to src/Common/src/CoreLib/Interop/Windows/Interop.BOOLEAN.cs
diff --git a/src/Common/src/CoreLib/Interop/Windows/Interop.Libraries.cs b/src/Common/src/CoreLib/Interop/Windows/Interop.Libraries.cs
index 398d18a2a0d2..8cbc8bfb266b 100644
--- a/src/Common/src/CoreLib/Interop/Windows/Interop.Libraries.cs
+++ b/src/Common/src/CoreLib/Interop/Windows/Interop.Libraries.cs
@@ -14,5 +14,7 @@ internal static partial class Libraries
         internal const string OleAut32 = "oleaut32.dll";
         internal const string User32 = "user32.dll";
         internal const string NtDll = "ntdll.dll";
+        internal const string Secur32 = "secur32.dll";
+        internal const string Shell32 = "shell32.dll";
     }
 }
diff --git a/src/Common/src/Interop/Windows/kernel32/Interop.ExpandEnvironmentStrings.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.ExpandEnvironmentStrings.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/kernel32/Interop.ExpandEnvironmentStrings.cs
rename to src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.ExpandEnvironmentStrings.cs
diff --git a/src/Common/src/Interop/Windows/kernel32/Interop.GetComputerName.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.GetComputerName.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/kernel32/Interop.GetComputerName.cs
rename to src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.GetComputerName.cs
diff --git a/src/Common/src/Interop/Windows/kernel32/Interop.GetCurrentDirectory.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.GetCurrentDirectory.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/kernel32/Interop.GetCurrentDirectory.cs
rename to src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.GetCurrentDirectory.cs
diff --git a/src/Common/src/Interop/Windows/kernel32/Interop.GetCurrentProcess_IntPtr.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.GetCurrentProcess_IntPtr.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/kernel32/Interop.GetCurrentProcess_IntPtr.cs
rename to src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.GetCurrentProcess_IntPtr.cs
diff --git a/src/Common/src/Interop/Windows/kernel32/Interop.GetLogicalDrive.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.GetLogicalDrives.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/kernel32/Interop.GetLogicalDrive.cs
rename to src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.GetLogicalDrives.cs
diff --git a/src/Common/src/Interop/Windows/kernel32/Interop.GetSystemDirectoryW.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.GetSystemDirectoryW.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/kernel32/Interop.GetSystemDirectoryW.cs
rename to src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.GetSystemDirectoryW.cs
diff --git a/src/Common/src/Interop/Windows/kernel32/Interop.GetSystemInfo.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.GetSystemInfo.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/kernel32/Interop.GetSystemInfo.cs
rename to src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.GetSystemInfo.cs
diff --git a/src/Common/src/Interop/Windows/kernel32/Interop.GetVersionExW.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.GetVersionExW.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/kernel32/Interop.GetVersionExW.cs
rename to src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.GetVersionExW.cs
diff --git a/src/Common/src/Interop/Windows/kernel32/Interop.IsWow64Process_IntPtr.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.IsWow64Process_IntPtr.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/kernel32/Interop.IsWow64Process_IntPtr.cs
rename to src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.IsWow64Process_IntPtr.cs
diff --git a/src/Common/src/Interop/Windows/kernel32/Interop.SYSTEM_INFO.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.SYSTEM_INFO.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/kernel32/Interop.SYSTEM_INFO.cs
rename to src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.SYSTEM_INFO.cs
diff --git a/src/Common/src/Interop/Windows/kernel32/Interop.SetCurrentDirectory.cs b/src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.SetCurrentDirectory.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/kernel32/Interop.SetCurrentDirectory.cs
rename to src/Common/src/CoreLib/Interop/Windows/Kernel32/Interop.SetCurrentDirectory.cs
diff --git a/src/Common/src/Interop/Windows/secur32/Interop.GetUserNameExW.cs b/src/Common/src/CoreLib/Interop/Windows/Secur32/Interop.GetUserNameExW.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/secur32/Interop.GetUserNameExW.cs
rename to src/Common/src/CoreLib/Interop/Windows/Secur32/Interop.GetUserNameExW.cs
diff --git a/src/Common/src/Interop/Windows/shell32/Interop.SHGetKnownFolderPath.cs b/src/Common/src/CoreLib/Interop/Windows/Shell32/Interop.SHGetKnownFolderPath.cs
similarity index 100%
rename from src/Common/src/Interop/Windows/shell32/Interop.SHGetKnownFolderPath.cs
rename to src/Common/src/CoreLib/Interop/Windows/Shell32/Interop.SHGetKnownFolderPath.cs
diff --git a/src/System.Runtime.Extensions/src/System/Environment.SpecialFolder.cs b/src/Common/src/CoreLib/System/Environment.SpecialFolder.cs
similarity index 100%
rename from src/System.Runtime.Extensions/src/System/Environment.SpecialFolder.cs
rename to src/Common/src/CoreLib/System/Environment.SpecialFolder.cs
diff --git a/src/System.Runtime.Extensions/src/System/Environment.SpecialFolderOption.cs b/src/Common/src/CoreLib/System/Environment.SpecialFolderOption.cs
similarity index 100%
rename from src/System.Runtime.Extensions/src/System/Environment.SpecialFolderOption.cs
rename to src/Common/src/CoreLib/System/Environment.SpecialFolderOption.cs
diff --git a/src/System.Runtime.Extensions/src/System/Environment.Unix.cs b/src/Common/src/CoreLib/System/Environment.Unix.cs
similarity index 100%
rename from src/System.Runtime.Extensions/src/System/Environment.Unix.cs
rename to src/Common/src/CoreLib/System/Environment.Unix.cs
diff --git a/src/System.Runtime.Extensions/src/System/Environment.Win32.cs b/src/Common/src/CoreLib/System/Environment.Win32.cs
similarity index 100%
rename from src/System.Runtime.Extensions/src/System/Environment.Win32.cs
rename to src/Common/src/CoreLib/System/Environment.Win32.cs
diff --git a/src/System.Runtime.Extensions/src/System/Environment.WinRT.cs b/src/Common/src/CoreLib/System/Environment.WinRT.cs
similarity index 100%
rename from src/System.Runtime.Extensions/src/System/Environment.WinRT.cs
rename to src/Common/src/CoreLib/System/Environment.WinRT.cs
diff --git a/src/System.Runtime.Extensions/src/System/Environment.Windows.cs b/src/Common/src/CoreLib/System/Environment.Windows.cs
similarity index 100%
rename from src/System.Runtime.Extensions/src/System/Environment.Windows.cs
rename to src/Common/src/CoreLib/System/Environment.Windows.cs
diff --git a/src/System.Runtime.Extensions/src/System/Environment.cs b/src/Common/src/CoreLib/System/Environment.cs
similarity index 100%
rename from src/System.Runtime.Extensions/src/System/Environment.cs
rename to src/Common/src/CoreLib/System/Environment.cs
diff --git a/src/Common/src/System/IO/DriveInfoInternal.Unix.cs b/src/Common/src/CoreLib/System/IO/DriveInfoInternal.Unix.cs
similarity index 100%
rename from src/Common/src/System/IO/DriveInfoInternal.Unix.cs
rename to src/Common/src/CoreLib/System/IO/DriveInfoInternal.Unix.cs
diff --git a/src/Common/src/System/IO/DriveInfoInternal.Win32.cs b/src/Common/src/CoreLib/System/IO/DriveInfoInternal.Windows.cs
similarity index 100%
rename from src/Common/src/System/IO/DriveInfoInternal.Win32.cs
rename to src/Common/src/CoreLib/System/IO/DriveInfoInternal.Windows.cs
diff --git a/src/Common/src/System/IO/PersistedFiles.Names.Unix.cs b/src/Common/src/CoreLib/System/IO/PersistedFiles.Names.Unix.cs
similarity index 100%
rename from src/Common/src/System/IO/PersistedFiles.Names.Unix.cs
rename to src/Common/src/CoreLib/System/IO/PersistedFiles.Names.Unix.cs
diff --git a/src/Common/src/System/IO/PersistedFiles.Unix.cs b/src/Common/src/CoreLib/System/IO/PersistedFiles.Unix.cs
similarity index 100%
rename from src/Common/src/System/IO/PersistedFiles.Unix.cs
rename to src/Common/src/CoreLib/System/IO/PersistedFiles.Unix.cs
diff --git a/src/System.Runtime.Extensions/src/System/OperatingSystem.cs b/src/Common/src/CoreLib/System/OperatingSystem.cs
similarity index 100%
rename from src/System.Runtime.Extensions/src/System/OperatingSystem.cs
rename to src/Common/src/CoreLib/System/OperatingSystem.cs
diff --git a/src/Common/src/System/PasteArguments.Unix.cs b/src/Common/src/CoreLib/System/PasteArguments.Unix.cs
similarity index 100%
rename from src/Common/src/System/PasteArguments.Unix.cs
rename to src/Common/src/CoreLib/System/PasteArguments.Unix.cs
diff --git a/src/Common/src/System/PasteArguments.Windows.cs b/src/Common/src/CoreLib/System/PasteArguments.Windows.cs
similarity index 100%
rename from src/Common/src/System/PasteArguments.Windows.cs
rename to src/Common/src/CoreLib/System/PasteArguments.Windows.cs
diff --git a/src/Common/src/System/PasteArguments.cs b/src/Common/src/CoreLib/System/PasteArguments.cs
similarity index 100%
rename from src/Common/src/System/PasteArguments.cs
rename to src/Common/src/CoreLib/System/PasteArguments.cs
diff --git a/src/System.Runtime.Extensions/src/System/PlatformID.cs b/src/Common/src/CoreLib/System/PlatformID.cs
similarity index 100%
rename from src/System.Runtime.Extensions/src/System/PlatformID.cs
rename to src/Common/src/CoreLib/System/PlatformID.cs
diff --git a/src/Common/tests/Common.Tests.csproj b/src/Common/tests/Common.Tests.csproj
index bc83e72e88dd..d0e7f85cd7eb 100644
--- a/src/Common/tests/Common.Tests.csproj
+++ b/src/Common/tests/Common.Tests.csproj
@@ -67,8 +67,8 @@
     <Compile Include="$(CommonPath)\System\Security\IdentityHelper.cs">
       <Link>Common\System\Security\IdentityHelper.cs</Link>
     </Compile>
-    <Compile Include="..\src\System\PasteArguments.cs">
-      <Link>Common\System\PasteArguments.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\PasteArguments.cs">
+      <Link>Common\CoreLib\System\PasteArguments.cs</Link>
     </Compile>
     <Compile Include="Tests\Interop\procfsTests.cs" />
     <Compile Include="Tests\System\CharArrayHelpersTests.cs" />
@@ -121,8 +121,8 @@
       <Link>Common\CoreLib\System\IO\Win32Marshal.cs</Link>
     </Compile>
     <Compile Include="Tests\System\IO\Win32Marshal.Tests.cs" />
-    <Compile Include="..\src\System\PasteArguments.Windows.cs">
-      <Link>Common\System\PasteArguments.Windows.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\PasteArguments.Windows.cs">
+      <Link>Common\CoreLib\System\PasteArguments.Windows.cs</Link>
     </Compile>
   </ItemGroup>
   <ItemGroup Condition="'$(TargetsUnix)'=='true'">
@@ -136,8 +136,8 @@
     <Compile Include="$(CommonPath)\Interop\Unix\Interop.Libraries.cs">
       <Link>Common\Interop\Unix\Interop.Libraries.cs</Link>
     </Compile>
-    <Compile Include="..\src\System\PasteArguments.Unix.cs">
-      <Link>Common\System\PasteArguments.Unix.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\PasteArguments.Unix.cs">
+      <Link>Common\CoreLib\System\PasteArguments.Unix.cs</Link>
     </Compile>
   </ItemGroup>
   <ItemGroup>
@@ -152,4 +152,4 @@
       <Name>RemoteExecutorConsoleApp</Name>
     </ProjectReference>
   </ItemGroup>
-</Project>
\ No newline at end of file
+</Project>
diff --git a/src/CoreFx.Private.TestUtilities/src/CoreFx.Private.TestUtilities.csproj b/src/CoreFx.Private.TestUtilities/src/CoreFx.Private.TestUtilities.csproj
index 3cc47bdc14be..01c627df1869 100644
--- a/src/CoreFx.Private.TestUtilities/src/CoreFx.Private.TestUtilities.csproj
+++ b/src/CoreFx.Private.TestUtilities/src/CoreFx.Private.TestUtilities.csproj
@@ -27,18 +27,18 @@
     <Compile Include="System\PlatformDetection.cs" />
     <Compile Include="System\PlatformDetection.Unix.cs" Condition="'$(TargetsWindows)' != 'true'" />
     <Compile Include="System\PlatformDetection.Windows.cs" Condition="'$(TargetsWindows)' == 'true'" />
-    <Compile Include="$(CommonPath)\System\PasteArguments.cs">
-      <Link>Common\System\PasteArguments.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\PasteArguments.cs">
+      <Link>Common\CoreLib\System\PasteArguments.cs</Link>
     </Compile>
     <Compile Include="System\AssertExtensions.cs" />
     <Compile Include="System\TheoryExtensions.cs" />
   </ItemGroup>
   <ItemGroup Condition="'$(TargetsWindows)' == 'true'">
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetCurrentProcess_IntPtr.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetCurrentProcess_IntPtr.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.GetCurrentProcess_IntPtr.cs</Link>
     </Compile>
-    <Compile Include="..\..\Common\src\System\PasteArguments.Windows.cs">
-      <Link>Common\System\PasteArguments.Windows.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\PasteArguments.Windows.cs">
+      <Link>Common\CoreLib\System\PasteArguments.Windows.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\NtDll\Interop.RTL_OSVERSIONINFOEX.cs">
       <Link>Common\Interop\Windows\NtDll\Interop.RTL_OSVERSIONINFOEX.cs</Link>
@@ -73,11 +73,11 @@
     <Compile Include="$(CommonPath)\Interop\Unix\System.Security.Cryptography.Native\Interop.OpenSslVersion.cs">
       <Link>Common\Interop\Unix\System.Security.Cryptography.Native\Interop.OpenSslVersion.cs</Link>
     </Compile>
-    <Compile Include="..\..\Common\src\System\PasteArguments.Unix.cs">
-      <Link>Common\System\PasteArguments.Unix.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\PasteArguments.Unix.cs">
+      <Link>Common\CoreLib\System\PasteArguments.Unix.cs</Link>
     </Compile>
     <Compile Include="System\AdminHelpers.Unix.cs" />
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetEUid.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetEUid.cs">
       <Link>Common\Interop\Unix\Interop.GetEUid.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\Interop.Libraries.cs">
diff --git a/src/Microsoft.IO.Redist/src/Microsoft.IO.Redist.csproj b/src/Microsoft.IO.Redist/src/Microsoft.IO.Redist.csproj
index 523b98f3765b..f09a51e70107 100644
--- a/src/Microsoft.IO.Redist/src/Microsoft.IO.Redist.csproj
+++ b/src/Microsoft.IO.Redist/src/Microsoft.IO.Redist.csproj
@@ -35,8 +35,8 @@
     <Compile Include="..\..\System.IO.FileSystem\src\System\IO\ReadLinesIterator.cs" Link="Microsoft\IO\ReadLinesIterator.cs" />
     <Compile Include="..\..\System.IO.FileSystem\src\System\IO\SearchOption.cs" Link="Microsoft\IO\SearchOption.cs" />
     <Compile Include="..\..\System.IO.FileSystem\src\System\IO\SearchTarget.cs" Link="Microsoft\IO\SearchTarget.cs" />
-    <Compile Include="$(CommonPath)\System\IO\DriveInfoInternal.Win32.cs">
-      <Link>Common\System\IO\DriveInfoInternal.Win32.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\IO\DriveInfoInternal.Windows.cs">
+      <Link>Common\System\IO\DriveInfoInternal.Windows.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\System\Memory\FixedBufferExtensions.cs">
       <Link>Common\System\Memory\FixedBufferExtensions.cs</Link>
@@ -53,7 +53,7 @@
     <Compile Include="$(CommonPath)\Interop\Windows\Interop.UNICODE_STRING.cs">
       <Link>Common\Interop\Windows\Interop.UNICODE_STRING.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\Interop.BOOLEAN.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\Interop.BOOLEAN.cs">
       <Link>Common\Interop\Windows\Interop.BOOLEAN.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\NtDll\Interop.IO_STATUS_BLOCK.cs">
@@ -128,8 +128,8 @@
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.DeleteVolumeMountPoint.cs">
       <Link>Common\Interop\Windows\Interop.DeleteVolumeMountPoint.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetLogicalDrive.cs">
-      <Link>Common\Interop\Windows\Interop.GetLogicalDrive.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetLogicalDrives.cs">
+      <Link>Common\Interop\Windows\Interop.GetLogicalDrives.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.SetFileInformationByHandle.cs">
       <Link>Common\Interop\Windows\Interop.SetFileInformationByHandle.cs</Link>
diff --git a/src/System.Console/src/System.Console.csproj b/src/System.Console/src/System.Console.csproj
index 72f2a0294ac0..818ae664e4ca 100644
--- a/src/System.Console/src/System.Console.csproj
+++ b/src/System.Console/src/System.Console.csproj
@@ -172,10 +172,10 @@
     <Compile Include="$(CommonPath)\Microsoft\Win32\SafeHandles\SafeFileHandleHelper.Unix.cs">
       <Link>Common\Microsoft\Win32\SafeHandles\SafeFileHandleHelper.Unix.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\System\IO\PersistedFiles.Unix.cs">
+    <Compile Include="$(CommonPath)\CoreLib\System\IO\PersistedFiles.Unix.cs">
       <Link>Common\System\IO\PersistedFiles.Unix.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\System\IO\PersistedFiles.Names.Unix.cs">
+    <Compile Include="$(CommonPath)\CoreLib\System\IO\PersistedFiles.Names.Unix.cs">
       <Link>Common\System\IO\PersistedFiles.Names.Unix.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\CoreLib\System\Text\StringBuilderCache.cs">
@@ -226,10 +226,10 @@
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.Poll.cs">
       <Link>Common\Interop\Unix\Interop.Poll.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetEUid.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetEUid.cs">
       <Link>Common\Interop\Unix\Interop.GetEUid.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetPwUid.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetPwUid.cs">
       <Link>Common\Interop\Unix\Interop.GetPwUid.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.RegisterForCtrlC.cs">
@@ -284,4 +284,4 @@
   <ItemGroup Condition="'$(TargetsUnix)' == 'true'">
     <Reference Include="System.Threading.Thread" />
   </ItemGroup>
-</Project>
\ No newline at end of file
+</Project>
diff --git a/src/System.Diagnostics.PerformanceCounter/src/System.Diagnostics.PerformanceCounter.csproj b/src/System.Diagnostics.PerformanceCounter/src/System.Diagnostics.PerformanceCounter.csproj
index 9d1cccb2ab7c..c43c9723d4c7 100644
--- a/src/System.Diagnostics.PerformanceCounter/src/System.Diagnostics.PerformanceCounter.csproj
+++ b/src/System.Diagnostics.PerformanceCounter/src/System.Diagnostics.PerformanceCounter.csproj
@@ -76,7 +76,7 @@
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.FreeLibrary.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.FreeLibrary.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetComputerName.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetComputerName.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.GetComputerName.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetCurrentProcess_SafeProcessHandle.cs">
diff --git a/src/System.Diagnostics.Process/src/System.Diagnostics.Process.csproj b/src/System.Diagnostics.Process/src/System.Diagnostics.Process.csproj
index 88620376e2a6..d6cebb976ce1 100644
--- a/src/System.Diagnostics.Process/src/System.Diagnostics.Process.csproj
+++ b/src/System.Diagnostics.Process/src/System.Diagnostics.Process.csproj
@@ -37,8 +37,8 @@
     <Compile Include="System\Diagnostics\ThreadWaitReason.cs" />
     <Compile Include="System\Diagnostics\MonitoringDescriptionAttribute.cs" />
     <Compile Include="System\Collections\Specialized\StringDictionaryWrapper.cs" />
-    <Compile Include="..\..\Common\src\System\PasteArguments.cs">
-      <Link>Common\System\PasteArguments.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\PasteArguments.cs">
+      <Link>Common\CoreLib\System\PasteArguments.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\Interop.Errors.cs">
       <Link>Common\Interop\Windows\Interop.Errors.cs</Link>
@@ -194,7 +194,7 @@
     <Compile Include="$(CommonPath)\Interop\Windows\advapi32\Interop.AdjustTokenPrivileges.cs">
       <Link>Common\Interop\Windows\advapi32\Interop.AdjustTokenPrivileges.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetComputerName.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetComputerName.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.GetComputerName.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetCurrentProcessId.cs">
@@ -302,10 +302,10 @@
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.Close.cs">
       <Link>Common\Interop\Unix\Interop.Close.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetHostName.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetHostName.cs">
       <Link>Common\Interop\Unix\Interop.GetHostName.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.SysConf.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.SysConf.cs">
       <Link>Common\Interop\Unix\Interop.SysConf.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.ForkAndExecProcess.cs">
@@ -317,7 +317,7 @@
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetPid.cs">
       <Link>Common\Interop\Unix\Interop.GetPid.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetPwUid.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetPwUid.cs">
       <Link>Common\Interop\Unix\Interop.GetPwUid.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetSetPriority.cs">
@@ -350,7 +350,7 @@
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.WaitPid.cs">
       <Link>Common\Interop\Unix\Interop.WaitPid.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.Access.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.Access.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.Access.cs</Link>
     </Compile>
   </ItemGroup>
@@ -450,4 +450,4 @@
     <Reference Include="System.Threading.Thread" />
     <Reference Include="System.Threading.ThreadPool" />
   </ItemGroup>
-</Project>
\ No newline at end of file
+</Project>
diff --git a/src/System.Diagnostics.Process/tests/Performance/System.Diagnostics.Process.PerformanceTests.csproj b/src/System.Diagnostics.Process/tests/Performance/System.Diagnostics.Process.PerformanceTests.csproj
index 4157ee56c6fd..9b0e5c8f5460 100644
--- a/src/System.Diagnostics.Process/tests/Performance/System.Diagnostics.Process.PerformanceTests.csproj
+++ b/src/System.Diagnostics.Process/tests/Performance/System.Diagnostics.Process.PerformanceTests.csproj
@@ -10,8 +10,8 @@
     <Compile Condition="'$(TargetGroup)' == 'uap'" Include="..\ProcessTestBase.Uap.cs" />
     <Compile Include="..\RemotelyInvokable.cs" />
     <Compile Include="Perf.Process.cs" />
-    <Compile Include="$(CommonPath)\System\PasteArguments.cs">
-      <Link>Common\System\PasteArguments.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\PasteArguments.cs">
+      <Link>Common\CoreLib\System\PasteArguments.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\System\IO\StringParser.cs">
       <Link>Common\System\IO\StringParser.cs</Link>
@@ -29,4 +29,4 @@
       <Name>PerfRunner</Name>
     </ProjectReference>
   </ItemGroup>
-</Project>
\ No newline at end of file
+</Project>
diff --git a/src/System.Diagnostics.Process/tests/System.Diagnostics.Process.Tests.csproj b/src/System.Diagnostics.Process/tests/System.Diagnostics.Process.Tests.csproj
index 07e38b048445..76a120215aec 100644
--- a/src/System.Diagnostics.Process/tests/System.Diagnostics.Process.Tests.csproj
+++ b/src/System.Diagnostics.Process/tests/System.Diagnostics.Process.Tests.csproj
@@ -6,8 +6,8 @@
     <Configurations>netcoreapp-Unix-Debug;netcoreapp-Unix-Release;netcoreapp-Windows_NT-Debug;netcoreapp-Windows_NT-Release;netstandard-Unix-Debug;netstandard-Unix-Release;netstandard-Windows_NT-Debug;netstandard-Windows_NT-Release;uap-Windows_NT-Debug;uap-Windows_NT-Release;uapaot-Windows_NT-Debug;uapaot-Windows_NT-Release</Configurations>
   </PropertyGroup>
   <ItemGroup>
-    <Compile Include="$(CommonPath)\System\PasteArguments.cs">
-      <Link>Common\System\PasteArguments.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\PasteArguments.cs">
+      <Link>Common\CoreLib\System\PasteArguments.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\System\IO\StringParser.cs">
       <Link>Common\System\IO\StringParser.cs</Link>
@@ -49,14 +49,14 @@
   </ItemGroup>
   <!-- WINDOWS: Shared CoreCLR and .NET Native -->
   <ItemGroup Condition="'$(TargetsWindows)' == 'true'">
-    <Compile Include="..\..\Common\src\System\PasteArguments.Windows.cs">
-      <Link>Common\System\PasteArguments.Windows.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\PasteArguments.Windows.cs">
+      <Link>Common\CoreLib\System\PasteArguments.Windows.cs</Link>
     </Compile>
   </ItemGroup>
   <!-- UNIX -->
   <ItemGroup Condition=" '$(TargetsUnix)' == 'true' ">
-    <Compile Include="..\..\Common\src\System\PasteArguments.Unix.cs">
-      <Link>Common\System\PasteArguments.Unix.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\PasteArguments.Unix.cs">
+      <Link>Common\CoreLib\System\PasteArguments.Unix.cs</Link>
     </Compile>
   </ItemGroup>
-</Project>
\ No newline at end of file
+</Project>
diff --git a/src/System.IO.FileSystem.DriveInfo/src/System.IO.FileSystem.DriveInfo.csproj b/src/System.IO.FileSystem.DriveInfo/src/System.IO.FileSystem.DriveInfo.csproj
index 46018ecd92cc..f7f1e37ddd95 100644
--- a/src/System.IO.FileSystem.DriveInfo/src/System.IO.FileSystem.DriveInfo.csproj
+++ b/src/System.IO.FileSystem.DriveInfo/src/System.IO.FileSystem.DriveInfo.csproj
@@ -29,8 +29,8 @@
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetVolumeInformation.cs">
       <Link>Common\Interop\Windows\Interop.GetVolumeInformation.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetLogicalDrive.cs">
-      <Link>Common\Interop\Windows\Interop.GetLogicalDrive.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetLogicalDrives.cs">
+      <Link>Common\Interop\Windows\Interop.GetLogicalDrives.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetDiskFreeSpaceEx.cs">
       <Link>Common\Interop\Windows\Interop.GetDiskFreeSpaceEx.cs</Link>
@@ -62,8 +62,8 @@
     <Compile Include="$(CommonPath)\CoreLib\System\IO\Win32Marshal.cs">
       <Link>Common\CoreLib\System\IO\Win32Marshal.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\System\IO\DriveInfoInternal.Win32.cs">
-      <Link>Common\System\IO\DriveInfoInternal.Win32.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\IO\DriveInfoInternal.Windows.cs">
+      <Link>Common\System\IO\DriveInfoInternal.Windows.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\System\IO\PathInternal.Windows.cs">
       <Link>Common\System\IO\PathInternal.Windows.cs</Link>
@@ -86,7 +86,7 @@
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.PathConf.cs">
       <Link>Common\Interop\Unix\Interop.PathConf.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.MountPoints.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.MountPoints.cs">
       <Link>Common\Interop\Unix\Interop.MountPoints.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.MountPoints.FormatInfo.cs">
@@ -104,4 +104,4 @@
     <Reference Include="System.Runtime.InteropServices" />
     <Reference Include="System.Threading.Tasks" />
   </ItemGroup>
-</Project>
\ No newline at end of file
+</Project>
diff --git a/src/System.IO.FileSystem/src/System.IO.FileSystem.csproj b/src/System.IO.FileSystem/src/System.IO.FileSystem.csproj
index e0a8861997d9..337020677d09 100644
--- a/src/System.IO.FileSystem/src/System.IO.FileSystem.csproj
+++ b/src/System.IO.FileSystem/src/System.IO.FileSystem.csproj
@@ -68,8 +68,8 @@
     <Compile Include="$(CommonPath)\System\HResults.cs">
       <Link>Common\System\HResults.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\System\IO\DriveInfoInternal.Win32.cs">
-      <Link>Common\System\IO\DriveInfoInternal.Win32.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\IO\DriveInfoInternal.Windows.cs">
+      <Link>Common\System\IO\DriveInfoInternal.Windows.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\CoreLib\System\IO\PathInternal.Windows.cs">
       <Link>Common\CoreLib\System\IO\PathInternal.Windows.cs</Link>
@@ -122,8 +122,8 @@
     <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\Kernel32\Interop.SetThreadErrorMode.cs">
       <Link>Common\CoreLib\Interop\Windows\Interop.SetThreadErrorMode.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetLogicalDrive.cs">
-      <Link>Common\Interop\Windows\Interop.GetLogicalDrive.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetLogicalDrives.cs">
+      <Link>Common\Interop\Windows\Interop.GetLogicalDrives.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.DeleteVolumeMountPoint.cs">
       <Link>Common\Interop\Windows\Interop.DeleteVolumeMountPoint.cs</Link>
@@ -187,7 +187,7 @@
     <Compile Include="$(CommonPath)\Interop\Windows\Interop.UNICODE_STRING.cs">
       <Link>Common\Interop\Windows\Interop.UNICODE_STRING.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\Interop.BOOLEAN.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\Interop.BOOLEAN.cs">
       <Link>Common\Interop\Windows\Interop.BOOLEAN.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\NtDll\Interop.IO_STATUS_BLOCK.cs">
@@ -261,7 +261,7 @@
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetEGid.cs">
       <Link>Common\Interop\Unix\Interop.GetEGid.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetEUid.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetEUid.cs">
       <Link>Common\Interop\Unix\Interop.GetEUid.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.Stat.cs">
@@ -276,7 +276,7 @@
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.Link.cs">
       <Link>Common\Interop\Unix\Interop.Link.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.MountPoints.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.MountPoints.cs">
       <Link>Common\Interop\Unix\Interop.MountPoints.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.Read.cs">
@@ -294,7 +294,7 @@
     <Compile Include="$(CommonPath)\CoreLib\System\IO\PathInternal.Unix.cs">
       <Link>Common\CoreLib\System\IO\PathInternal.Unix.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\System\IO\DriveInfoInternal.Unix.cs">
+    <Compile Include="$(CommonPath)\CoreLib\System\IO\DriveInfoInternal.Unix.cs">
       <Link>Common\System\IO\DriveInfoInternal.Unix.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\System\Text\ValueUtf8Converter.cs">
diff --git a/src/System.IO.MemoryMappedFiles/src/System.IO.MemoryMappedFiles.csproj b/src/System.IO.MemoryMappedFiles/src/System.IO.MemoryMappedFiles.csproj
index 14d3d961901e..38d4b38ea4c1 100644
--- a/src/System.IO.MemoryMappedFiles/src/System.IO.MemoryMappedFiles.csproj
+++ b/src/System.IO.MemoryMappedFiles/src/System.IO.MemoryMappedFiles.csproj
@@ -80,10 +80,10 @@
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GenericOperations.cs">
       <Link>Common\Interop\Windows\Interop.GenericOperations.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetSystemInfo.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetSystemInfo.cs">
       <Link>Common\Interop\Windows\Interop.GetSystemInfo.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.SYSTEM_INFO.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.SYSTEM_INFO.cs">
       <Link>Common\Interop\Windows\Interop.SYSTEM_INFO.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.HandleOptions.cs">
@@ -149,7 +149,7 @@
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.Permissions.cs">
       <Link>Common\Interop\Unix\Interop.Permissions.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.SysConf.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.SysConf.cs">
       <Link>Common\Interop\Unix\Interop.SysConf.cs</Link>
     </Compile>
     <Compile Include="Microsoft\Win32\SafeMemoryMappedFileHandle.Unix.cs" />
diff --git a/src/System.IO.Pipes/src/System.IO.Pipes.csproj b/src/System.IO.Pipes/src/System.IO.Pipes.csproj
index a8e36104d2a7..845787cefb25 100644
--- a/src/System.IO.Pipes/src/System.IO.Pipes.csproj
+++ b/src/System.IO.Pipes/src/System.IO.Pipes.csproj
@@ -64,7 +64,7 @@
     <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\Kernel32\Interop.FileTypes.cs">
       <Link>Common\CoreLib\Interop\Windows\Interop.FileTypes.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetCurrentProcess_IntPtr.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetCurrentProcess_IntPtr.cs">
       <Link>Common\Interop\Windows\Interop.GetCurrentProcess.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.DuplicateHandle_IntPtr.cs">
@@ -186,7 +186,7 @@
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.FLock.cs">
       <Link>Common\Interop\Unix\Interop.FLock.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetHostName.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetHostName.cs">
       <Link>Common\Interop\Unix\Interop.GetHostName.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetPeerUserName.cs">
@@ -228,7 +228,7 @@
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetPeerID.cs">
       <Link>Common\Interop\Unix\Interop.GetPeerID.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetEUid.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetEUid.cs">
       <Link>Common\Interop\Unix\Interop.GetEUid.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.SetEUid.cs">
diff --git a/src/System.Net.NameResolution/src/System.Net.NameResolution.csproj b/src/System.Net.NameResolution/src/System.Net.NameResolution.csproj
index 67e4fa5456e7..772b5b23b9a3 100644
--- a/src/System.Net.NameResolution/src/System.Net.NameResolution.csproj
+++ b/src/System.Net.NameResolution/src/System.Net.NameResolution.csproj
@@ -162,7 +162,7 @@
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.Close.cs">
       <Link>Interop\Unix\System.Native\Interop.Close.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetHostName.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetHostName.cs">
       <Link>Interop\Unix\System.Native\Interop.GetHostName.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetNameInfo.cs">
diff --git a/src/System.Net.NameResolution/tests/PalTests/System.Net.NameResolution.Pal.Tests.csproj b/src/System.Net.NameResolution/tests/PalTests/System.Net.NameResolution.Pal.Tests.csproj
index c5013d11a5d9..0c9a3b7dc181 100644
--- a/src/System.Net.NameResolution/tests/PalTests/System.Net.NameResolution.Pal.Tests.csproj
+++ b/src/System.Net.NameResolution/tests/PalTests/System.Net.NameResolution.Pal.Tests.csproj
@@ -167,7 +167,7 @@
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.Close.cs">
       <Link>Interop\Unix\System.Native\Interop.Close.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetHostName.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetHostName.cs">
       <Link>Interop\Unix\System.Native\Interop.GetHostName.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetNameInfo.cs">
diff --git a/src/System.Net.NetworkInformation/src/System.Net.NetworkInformation.csproj b/src/System.Net.NetworkInformation/src/System.Net.NetworkInformation.csproj
index 852b4858695e..c77c9eefc648 100644
--- a/src/System.Net.NetworkInformation/src/System.Net.NetworkInformation.csproj
+++ b/src/System.Net.NetworkInformation/src/System.Net.NetworkInformation.csproj
@@ -176,7 +176,7 @@
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetDomainName.cs">
       <Link>Interop\Unix\System.Native\Interop.GetDomainName.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetHostName.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetHostName.cs">
       <Link>Interop\Unix\System.Native\Interop.GetHostName.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.MapTcpState.cs">
diff --git a/src/System.Net.Primitives/src/System.Net.Primitives.csproj b/src/System.Net.Primitives/src/System.Net.Primitives.csproj
index 18490df709ab..ef986cafb0bc 100644
--- a/src/System.Net.Primitives/src/System.Net.Primitives.csproj
+++ b/src/System.Net.Primitives/src/System.Net.Primitives.csproj
@@ -164,7 +164,7 @@
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetDomainName.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.GetDomainName.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetHostName.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetHostName.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.GetHostName.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetNameInfo.cs">
diff --git a/src/System.Net.Primitives/tests/PalTests/System.Net.Primitives.Pal.Tests.csproj b/src/System.Net.Primitives/tests/PalTests/System.Net.Primitives.Pal.Tests.csproj
index 51942a23da69..398277621ae5 100644
--- a/src/System.Net.Primitives/tests/PalTests/System.Net.Primitives.Pal.Tests.csproj
+++ b/src/System.Net.Primitives/tests/PalTests/System.Net.Primitives.Pal.Tests.csproj
@@ -141,7 +141,7 @@
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetDomainName.cs">
       <Link>ProductionCode\Common\Interop\Unix\System.Native\Interop.GetDomainName.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetHostName.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetHostName.cs">
       <Link>ProductionCode\Common\Interop\Unix\System.Native\Interop.GetHostName.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetNameInfo.cs">
diff --git a/src/System.Runtime.Extensions/src/System.Runtime.Extensions.csproj b/src/System.Runtime.Extensions/src/System.Runtime.Extensions.csproj
index 997f3b411732..49230890d42b 100644
--- a/src/System.Runtime.Extensions/src/System.Runtime.Extensions.csproj
+++ b/src/System.Runtime.Extensions/src/System.Runtime.Extensions.csproj
@@ -10,8 +10,8 @@
     <Configurations>netcoreapp-Unix-Debug;netcoreapp-Unix-Release;netcoreapp-Windows_NT-Debug;netcoreapp-Windows_NT-Release;netcoreappaot-Windows_NT-Debug;netcoreappaot-Windows_NT-Release;uap-Windows_NT-Debug;uap-Windows_NT-Release;uapaot-Windows_NT-Debug;uapaot-Windows_NT-Release</Configurations>
   </PropertyGroup>
   <ItemGroup>
-    <Compile Include="..\..\Common\src\System\PasteArguments.cs">
-      <Link>Common\System\PasteArguments.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\PasteArguments.cs">
+      <Link>Common\CoreLib\System\PasteArguments.cs</Link>
     </Compile>
     <Compile Include="System\AppDomain.cs" />
     <Compile Include="System\AppDomainSetup.cs" />
@@ -21,13 +21,23 @@
     <Compile Include="System\CodeDom\Compiler\IndentedTextWriter.cs" />
     <Compile Include="System\Context.cs" />
     <Compile Include="System\Diagnostics\Stopwatch.cs" />
-    <Compile Include="System\Environment.cs" />
-    <Compile Include="System\Environment.SpecialFolder.cs" />
-    <Compile Include="System\Environment.SpecialFolderOption.cs" />
+    <Compile Include="$(CommonPath)\CoreLib\System\Environment.cs">
+      <Link>Common\CoreLib\System\Environment.cs</Link>
+    </Compile>
+    <Compile Include="$(CommonPath)\CoreLib\System\Environment.SpecialFolder.cs">
+      <Link>Common\CoreLib\System\Environment.SpecialFolder.cs</Link>
+    </Compile>
+    <Compile Include="$(CommonPath)\CoreLib\System\Environment.SpecialFolderOption.cs">
+      <Link>Common\CoreLib\System\Environment.SpecialFolderOption.cs</Link>
+    </Compile>
     <Compile Include="System\LoaderOptimization.cs" />
     <Compile Include="System\LoaderOptimizationAttribute.cs" />
-    <Compile Include="System\OperatingSystem.cs" />
-    <Compile Include="System\PlatformID.cs" />
+    <Compile Include="$(CommonPath)\CoreLib\System\OperatingSystem.cs">
+      <Link>Common\CoreLib\System\OperatingSystem.cs</Link>
+    </Compile>
+    <Compile Include="$(CommonPath)\CoreLib\System\PlatformID.cs">
+      <Link>Common\CoreLib\System\PlatformID.cs</Link>
+    </Compile>
     <Compile Include="System\IO\StringReader.cs" />
     <Compile Include="System\IO\StringWriter.cs" />
     <Compile Include="System\IO\BufferedStream.cs" />
@@ -69,23 +79,29 @@
     </Compile>
   </ItemGroup>
   <ItemGroup Condition="'$(TargetGroup)' == 'uapaot' or '$(TargetGroup)' == 'uap'">
-    <Compile Include="System\Environment.WinRT.cs" />
+    <Compile Include="$(CommonPath)\CoreLib\System\Environment.WinRT.cs">
+      <Link>Common\CoreLib\System\Environment.WinRT.cs</Link>
+    </Compile>
   </ItemGroup>
   <ItemGroup Condition="'$(TargetsWindows)' == 'true' and '$(TargetGroup)' != 'uapaot' and '$(TargetGroup)' != 'uap'">
-    <Compile Include="System\Environment.Win32.cs" />
-    <Compile Include="$(CommonPath)\Interop\Windows\secur32\Interop.GetUserNameExW.cs">
+    <Compile Include="$(CommonPath)\CoreLib\System\Environment.Win32.cs">
+      <Link>Common\CoreLib\System\Environment.Win32.cs</Link>
+    </Compile>
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\secur32\Interop.GetUserNameExW.cs">
       <Link>Common\Interop\Windows\secur32\Interop.GetUserNameExW.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\shell32\Interop.SHGetKnownFolderPath.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\shell32\Interop.SHGetKnownFolderPath.cs">
       <Link>Common\Interop\Windows\shell32\Interop.SHGetKnownFolderPath.cs</Link>
     </Compile>
   </ItemGroup>
   <!-- WINDOWS: Shared CoreCLR and .NET Native -->
   <ItemGroup Condition="'$(TargetsWindows)' == 'true'">
-    <Compile Include="..\..\Common\src\System\PasteArguments.Windows.cs">
-      <Link>Common\System\PasteArguments.Windows.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\PasteArguments.Windows.cs">
+      <Link>Common\CoreLib\System\PasteArguments.Windows.cs</Link>
+    </Compile>
+    <Compile Include="$(CommonPath)\CoreLib\System\Environment.Windows.cs">
+      <Link>Common\CoreLib\System\Environment.Windows.cs</Link>
     </Compile>
-    <Compile Include="System\Environment.Windows.cs" />
     <Compile Include="System\Runtime\Versioning\VersioningHelper.Windows.cs" />
     <Compile Include="System\Diagnostics\Stopwatch.Windows.cs" />
     <Compile Include="$(CommonPath)\CoreLib\System\IO\Win32Marshal.cs">
@@ -97,43 +113,43 @@
     <Compile Include="$(CommonPath)\Interop\Windows\Interop.Errors.cs">
       <Link>Common\Interop\Windows\Interop.Errors.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\Interop.BOOLEAN.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\Interop.BOOLEAN.cs">
       <Link>Common\Interop\Windows\Interop.BOOLEAN.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\advapi32\Interop.LookupAccountNameW.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\advapi32\Interop.LookupAccountNameW.cs">
       <Link>Common\Interop\Windows\advapi32\Interop.LookupAccountNameW.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetComputerName.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetComputerName.cs">
       <Link>Common\Interop\Windows\mincore\Interop.GetComputerNameW.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetCurrentProcess_IntPtr.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetCurrentProcess_IntPtr.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.GetCurrentProcess_IntPtr.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetCurrentProcessId.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.GetCurrentProcessId.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.ExpandEnvironmentStrings.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.ExpandEnvironmentStrings.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.ExpandEnvironmentStrings.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\Kernel32\Interop.FormatMessage.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.FormatMessage.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetCurrentDirectory.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetCurrentDirectory.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.GetCurrentDirectory.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetLogicalDrive.cs">
-      <Link>Common\Interop\Windows\Interop.GetLogicalDrive.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetLogicalDrives.cs">
+      <Link>Common\Interop\Windows\Interop.GetLogicalDrives.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetSystemDirectoryW.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetSystemDirectoryW.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.GetSystemDirectoryW.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetSystemInfo.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetSystemInfo.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.GetSystemInfo.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetVersionExW.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetVersionExW.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.GetVersionExW.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.IsWow64Process_IntPtr.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.IsWow64Process_IntPtr.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.IsWow64Process_IntPtr.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.MaxLengths.cs">
@@ -145,14 +161,14 @@
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.QueryPerformanceFrequency.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.QueryPerformanceFrequency.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.SetCurrentDirectory.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.SetCurrentDirectory.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.SetCurrentDirectory.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.SYSTEM_INFO.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.SYSTEM_INFO.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.SYSTEM_INFO.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\System\IO\DriveInfoInternal.Win32.cs">
-      <Link>Common\System\IO\DriveInfoInternal.Win32.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\IO\DriveInfoInternal.Windows.cs">
+      <Link>Common\System\IO\DriveInfoInternal.Windows.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\CoreLib\System\IO\PathHelper.Windows.cs">
       <Link>CoreLib\System\IO\PathHelper.Windows.cs</Link>
@@ -172,7 +188,9 @@
   </ItemGroup>
   <!-- UNIX -->
   <ItemGroup Condition=" '$(TargetsUnix)' == 'true' ">
-    <Compile Include="System\Environment.Unix.cs" />
+    <Compile Include="$(CommonPath)\CoreLib\System\Environment.Unix.cs">
+      <Link>Common\CoreLib\System\Environment.Unix.cs</Link>
+    </Compile>
     <Compile Include="System\Runtime\Versioning\VersioningHelper.Unix.cs" />
     <Compile Include="System\Diagnostics\Stopwatch.Unix.cs" />
     <Compile Include="$(CommonPath)\Interop\OSX\Interop.Libraries.cs">
@@ -190,10 +208,10 @@
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetPid.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.GetPid.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.Access.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.Access.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.Access.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.ChDir.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.ChDir.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.ChDir.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.Close.cs">
@@ -202,47 +220,47 @@
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetCwd.cs">
       <Link>Common\CoreLib\Interop\Unix\System.Native\Interop.GetCwd.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetEUid.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetEUid.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.GetEUid.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetHostName.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetHostName.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.GetHostName.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetTimestamp.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.GetTimestamp.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetPwUid.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetPwUid.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.GetPwUid.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetUnixName.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetUnixName.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.GetUnixName.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetUnixRelease.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetUnixRelease.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.GetUnixRelease.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.MksTemps.cs">
       <Link>Common\CoreLib\Interop\Unix\System.Native\Interop.MksTemps.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.MountPoints.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.MountPoints.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.MountPoints.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.PathConf.cs">
       <Link>Common\CoreLib\Interop\Unix\System.Native\Interop.PathConf.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.SysConf.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.SysConf.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.SysConf.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\System\IO\DriveInfoInternal.Unix.cs">
+    <Compile Include="$(CommonPath)\CoreLib\System\IO\DriveInfoInternal.Unix.cs">
       <Link>Common\System\IO\DriveInfoInternal.Unix.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\System\IO\PersistedFiles.Unix.cs">
+    <Compile Include="$(CommonPath)\CoreLib\System\IO\PersistedFiles.Unix.cs">
       <Link>Common\System\IO\PersistedFiles.Unix.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\System\IO\PersistedFiles.Names.Unix.cs">
+    <Compile Include="$(CommonPath)\CoreLib\System\IO\PersistedFiles.Names.Unix.cs">
       <Link>Common\System\IO\PersistedFiles.Unix.cs</Link>
     </Compile>
-    <Compile Include="..\..\Common\src\System\PasteArguments.Unix.cs">
-      <Link>Common\System\PasteArguments.Unix.cs</Link>
+    <Compile Include="$(CommonPath)\CoreLib\System\PasteArguments.Windows.cs">
+      <Link>Common\CoreLib\System\PasteArguments.Windows.cs</Link>
     </Compile>
   </ItemGroup>
   <ItemGroup>
diff --git a/src/System.Runtime.InteropServices.RuntimeInformation/src/System.Runtime.InteropServices.RuntimeInformation.csproj b/src/System.Runtime.InteropServices.RuntimeInformation/src/System.Runtime.InteropServices.RuntimeInformation.csproj
index e2b0639afdb0..efaa03b1f452 100644
--- a/src/System.Runtime.InteropServices.RuntimeInformation/src/System.Runtime.InteropServices.RuntimeInformation.csproj
+++ b/src/System.Runtime.InteropServices.RuntimeInformation/src/System.Runtime.InteropServices.RuntimeInformation.csproj
@@ -12,7 +12,7 @@
   </ItemGroup>
   <ItemGroup Condition="'$(TargetsUnix)' == 'true'">
     <Compile Include="System\Runtime\InteropServices\RuntimeInformation\RuntimeInformation.Unix.cs" />
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetUnixName.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetUnixName.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.GetUnixName.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetUnixVersion.cs">
@@ -47,10 +47,10 @@
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetNativeSystemInfo.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.GetNativeSystemInfo.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.SYSTEM_INFO.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.SYSTEM_INFO.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.SYSTEM_INFO.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetSystemInfo.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetSystemInfo.cs">
       <Link>Common\Interop\Windows\kernel32\Interop.GetSystemInfo.cs</Link>
     </Compile>
   </ItemGroup>
@@ -63,4 +63,4 @@
     <Reference Include="System.Runtime.InteropServices" />
     <Reference Include="System.Threading" />
   </ItemGroup>
-</Project>
\ No newline at end of file
+</Project>
diff --git a/src/System.Security.AccessControl/src/System.Security.AccessControl.csproj b/src/System.Security.AccessControl/src/System.Security.AccessControl.csproj
index 3eff7d55eecb..bcf4c73fc7da 100644
--- a/src/System.Security.AccessControl/src/System.Security.AccessControl.csproj
+++ b/src/System.Security.AccessControl/src/System.Security.AccessControl.csproj
@@ -89,7 +89,7 @@
     <Compile Include="$(CommonPath)\Interop\Windows\advapi32\Interop.OpenProcessToken_IntPtr.cs">
       <Link>Common\Interop\Interop.OpenProcessToken_IntPtrs.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetCurrentProcess_IntPtr.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetCurrentProcess_IntPtr.cs">
       <Link>Common\Interop\Interop.GetCurrentProcess_IntPtr.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\advapi32\Interop.SetThreadToken.cs">
@@ -120,4 +120,4 @@
     <Reference Include="System.Threading.Thread" />
     <Reference Include="Microsoft.Win32.Primitives" />
   </ItemGroup>
-</Project>
\ No newline at end of file
+</Project>
diff --git a/src/System.Security.Cryptography.X509Certificates/src/System.Security.Cryptography.X509Certificates.csproj b/src/System.Security.Cryptography.X509Certificates/src/System.Security.Cryptography.X509Certificates.csproj
index e42357be788c..9ebb714b66c6 100644
--- a/src/System.Security.Cryptography.X509Certificates/src/System.Security.Cryptography.X509Certificates.csproj
+++ b/src/System.Security.Cryptography.X509Certificates/src/System.Security.Cryptography.X509Certificates.csproj
@@ -390,10 +390,10 @@
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.FChMod.cs">
       <Link>Common\Interop\Unix\System.Native\Interop.FChMod.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetEUid.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetEUid.cs">
       <Link>Common\Interop\Unix\Interop.GetEUid.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetPwUid.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetPwUid.cs">
       <Link>Common\Interop\Unix\Interop.GetPwUid.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.Stat.cs">
@@ -432,10 +432,10 @@
     <Compile Include="$(CommonPath)\System\Collections\Generic\ReferenceEqualityComparer.cs">
       <Link>Common\System\Collections\Generic\ReferenceEqualityComparer.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\System\IO\PersistedFiles.Unix.cs">
+    <Compile Include="$(CommonPath)\CoreLib\System\IO\PersistedFiles.Unix.cs">
       <Link>Common\System\IO\PersistedFiles.Unix.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\System\IO\PersistedFiles.Names.Unix.cs">
+    <Compile Include="$(CommonPath)\CoreLib\System\IO\PersistedFiles.Names.Unix.cs">
       <Link>Common\System\IO\PersistedFiles.Names.Unix.cs</Link>
     </Compile>
   </ItemGroup>
diff --git a/src/System.Security.Cryptography.X509Certificates/tests/System.Security.Cryptography.X509Certificates.Tests.csproj b/src/System.Security.Cryptography.X509Certificates/tests/System.Security.Cryptography.X509Certificates.Tests.csproj
index b74b308d2bd0..370d12262c28 100644
--- a/src/System.Security.Cryptography.X509Certificates/tests/System.Security.Cryptography.X509Certificates.Tests.csproj
+++ b/src/System.Security.Cryptography.X509Certificates/tests/System.Security.Cryptography.X509Certificates.Tests.csproj
@@ -61,10 +61,10 @@
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\Interop.Errors.cs">
       <Link>Common\CoreLib\Interop\Unix\Interop.Errors.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetEUid.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetEUid.cs">
       <Link>Common\Interop\Unix\Interop.GetEUid.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.GetPwUid.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.GetPwUid.cs">
       <Link>Common\Interop\Unix\Interop.GetPwUid.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Unix\System.Native\Interop.FChMod.cs">
@@ -76,10 +76,10 @@
     <Compile Include="$(CommonPath)\CoreLib\Interop\Unix\System.Native\Interop.Stat.cs">
       <Link>Common\CoreLib\Interop\Unix\System.Native\Interop.Stat.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\System\IO\PersistedFiles.Unix.cs">
+    <Compile Include="$(CommonPath)\CoreLib\System\IO\PersistedFiles.Unix.cs">
       <Link>Common\System\IO\PersistedFiles.Unix.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\System\IO\PersistedFiles.Names.Unix.cs">
+    <Compile Include="$(CommonPath)\CoreLib\System\IO\PersistedFiles.Names.Unix.cs">
       <Link>Common\System\IO\PersistedFiles.Names.Unix.cs</Link>
     </Compile>
     <Compile Include="HostnameMatchTests.Unix.cs" />
@@ -133,4 +133,4 @@
   <ItemGroup>
     <SupplementalTestData Include="$(PackagesDir)system.security.cryptography.x509certificates.testdata\1.0.2-prerelease\content\**\*.*" />
   </ItemGroup>
-</Project>
\ No newline at end of file
+</Project>
diff --git a/src/System.Security.Principal.Windows/src/System.Security.Principal.Windows.csproj b/src/System.Security.Principal.Windows/src/System.Security.Principal.Windows.csproj
index e0e538da06e2..81a303d09202 100644
--- a/src/System.Security.Principal.Windows/src/System.Security.Principal.Windows.csproj
+++ b/src/System.Security.Principal.Windows/src/System.Security.Principal.Windows.csproj
@@ -44,7 +44,7 @@
     <Compile Include="$(CommonPath)\Interop\Windows\sspicli\Interop.UNICODE_STRING.cs">
       <Link>Common\Interop\Interop.UNICODE_STRING.cs</Link>
     </Compile>
-    <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetCurrentProcess_IntPtr.cs">
+    <Compile Include="$(CommonPath)\CoreLib\Interop\Windows\kernel32\Interop.GetCurrentProcess_IntPtr.cs">
       <Link>Common\Interop\Interop.GetCurrentProcess.cs</Link>
     </Compile>
     <Compile Include="$(CommonPath)\Interop\Windows\kernel32\Interop.GetCurrentThread.cs">
@@ -197,4 +197,4 @@
     <Reference Include="System.Security.Principal" />
     <Reference Include="System.Threading" />
   </ItemGroup>
-</Project>
\ No newline at end of file
+</Project>