diff --git a/src/Tasks/GetFrameworkPath.cs b/src/Tasks/GetFrameworkPath.cs
index 93ac97f1f62..135319a5221 100644
--- a/src/Tasks/GetFrameworkPath.cs
+++ b/src/Tasks/GetFrameworkPath.cs
@@ -12,6 +12,7 @@ namespace Microsoft.Build.Tasks
     /// <summary>
     /// Returns the paths to the various frameworks versions.
     /// </summary>
+    [MSBuildMultiThreadableTask]
     public class GetFrameworkPath : TaskExtension
     {
         #region ITask Members
diff --git a/src/Tasks/GetFrameworkSDKPath.cs b/src/Tasks/GetFrameworkSDKPath.cs
index 05f35b77b96..0161001d0e8 100644
--- a/src/Tasks/GetFrameworkSDKPath.cs
+++ b/src/Tasks/GetFrameworkSDKPath.cs
@@ -18,18 +18,20 @@ namespace Microsoft.Build.Tasks
     /// <summary>
     /// Returns paths to the frameworks SDK.
     /// </summary>
+    [MSBuildMultiThreadableTask]
     public class GetFrameworkSdkPath : TaskExtension, IGetFrameworkSdkPathTaskContract
     {
         #region Properties
 
-        private static string s_path;
-        private static string s_version20Path;
-        private static string s_version35Path;
-        private static string s_version40Path;
-        private static string s_version45Path;
-        private static string s_version451Path;
-        private static string s_version46Path;
-        private static string s_version461Path;
+        private static volatile string s_path;
+        private static volatile string s_version20Path;
+        private static volatile string s_version35Path;
+        private static volatile string s_version40Path;
+        private static volatile string s_version45Path;
+        private static volatile string s_version451Path;
+        private static volatile string s_version46Path;
+        private static volatile string s_version461Path;
+        private static readonly LockType s_lockObject = new();
 
         /// <summary>
         /// The path to the latest .NET SDK if it could be found. It will be String.Empty if the SDK was not found.
@@ -39,28 +41,38 @@ public string Path
         {
             get
             {
-                if (s_path == null)
+                string path = s_path;
+                if (path == null)
                 {
-                    s_path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Latest, VisualStudioVersion.VersionLatest);
-
-                    if (String.IsNullOrEmpty(s_path))
-                    {
-                        Log.LogMessageFromResources(
-                            MessageImportance.High,
-                            "GetFrameworkSdkPath.CouldNotFindSDK",
-                            ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Latest, VisualStudioVersion.VersionLatest),
-                            ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Latest, VisualStudioVersion.VersionLatest));
-
-                        s_path = String.Empty;
-                    }
-                    else
+                    lock (s_lockObject)
                     {
-                        s_path = FrameworkFileUtilities.EnsureTrailingSlash(s_path);
-                        Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", s_path);
+                        path = s_path;
+                        if (path == null)
+                        {
+                            path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Latest, VisualStudioVersion.VersionLatest);
+
+                            if (String.IsNullOrEmpty(path))
+                            {
+                                Log.LogMessageFromResources(
+                                    MessageImportance.High,
+                                    "GetFrameworkSdkPath.CouldNotFindSDK",
+                                    ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Latest, VisualStudioVersion.VersionLatest),
+                                    ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Latest, VisualStudioVersion.VersionLatest));
+
+                                path = String.Empty;
+                            }
+                            else
+                            {
+                                path = FrameworkFileUtilities.EnsureTrailingSlash(path);
+                                Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", path);
+                            }
+                            
+                            s_path = path;
+                        }
                     }
                 }
 
-                return s_path;
+                return path;
             }
             set
             {
@@ -76,28 +88,38 @@ public string FrameworkSdkVersion20Path
         {
             get
             {
-                if (s_version20Path == null)
+                string path = s_version20Path;
+                if (path == null)
                 {
-                    s_version20Path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Version20);
-
-                    if (String.IsNullOrEmpty(s_version20Path))
-                    {
-                        Log.LogMessageFromResources(
-                            MessageImportance.High,
-                            "GetFrameworkSdkPath.CouldNotFindSDK",
-                            ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Version20),
-                            ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Version20));
-
-                        s_version20Path = String.Empty;
-                    }
-                    else
+                    lock (s_lockObject)
                     {
-                        s_version20Path = FrameworkFileUtilities.EnsureTrailingSlash(s_version20Path);
-                        Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", s_version20Path);
+                        path = s_version20Path;
+                        if (path == null)
+                        {
+                            path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Version20);
+
+                            if (String.IsNullOrEmpty(path))
+                            {
+                                Log.LogMessageFromResources(
+                                    MessageImportance.High,
+                                    "GetFrameworkSdkPath.CouldNotFindSDK",
+                                    ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Version20),
+                                    ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Version20));
+
+                                path = String.Empty;
+                            }
+                            else
+                            {
+                                path = FrameworkFileUtilities.EnsureTrailingSlash(path);
+                                Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", path);
+                            }
+                            
+                            s_version20Path = path;
+                        }
                     }
                 }
 
-                return s_version20Path;
+                return path;
             }
         }
 
@@ -109,28 +131,38 @@ public string FrameworkSdkVersion35Path
         {
             get
             {
-                if (s_version35Path == null)
+                string path = s_version35Path;
+                if (path == null)
                 {
-                    s_version35Path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Version35, VisualStudioVersion.VersionLatest);
-
-                    if (String.IsNullOrEmpty(s_version35Path))
-                    {
-                        Log.LogMessageFromResources(
-                            MessageImportance.High,
-                            "GetFrameworkSdkPath.CouldNotFindSDK",
-                            ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Version35, VisualStudioVersion.VersionLatest),
-                            ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Version35, VisualStudioVersion.VersionLatest));
-
-                        s_version35Path = String.Empty;
-                    }
-                    else
+                    lock (s_lockObject)
                     {
-                        s_version35Path = FrameworkFileUtilities.EnsureTrailingSlash(s_version35Path);
-                        Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", s_version35Path);
+                        path = s_version35Path;
+                        if (path == null)
+                        {
+                            path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Version35, VisualStudioVersion.VersionLatest);
+
+                            if (String.IsNullOrEmpty(path))
+                            {
+                                Log.LogMessageFromResources(
+                                    MessageImportance.High,
+                                    "GetFrameworkSdkPath.CouldNotFindSDK",
+                                    ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Version35, VisualStudioVersion.VersionLatest),
+                                    ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Version35, VisualStudioVersion.VersionLatest));
+
+                                path = String.Empty;
+                            }
+                            else
+                            {
+                                path = FrameworkFileUtilities.EnsureTrailingSlash(path);
+                                Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", path);
+                            }
+                            
+                            s_version35Path = path;
+                        }
                     }
                 }
 
-                return s_version35Path;
+                return path;
             }
         }
 
@@ -142,28 +174,38 @@ public string FrameworkSdkVersion40Path
         {
             get
             {
-                if (s_version40Path == null)
+                string path = s_version40Path;
+                if (path == null)
                 {
-                    s_version40Path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Version40, VisualStudioVersion.VersionLatest);
-
-                    if (String.IsNullOrEmpty(s_version40Path))
-                    {
-                        Log.LogMessageFromResources(
-                            MessageImportance.High,
-                            "GetFrameworkSdkPath.CouldNotFindSDK",
-                            ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Version40, VisualStudioVersion.VersionLatest),
-                            ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Version40, VisualStudioVersion.VersionLatest));
-
-                        s_version40Path = String.Empty;
-                    }
-                    else
+                    lock (s_lockObject)
                     {
-                        s_version40Path = FrameworkFileUtilities.EnsureTrailingSlash(s_version40Path);
-                        Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", s_version40Path);
+                        path = s_version40Path;
+                        if (path == null)
+                        {
+                            path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Version40, VisualStudioVersion.VersionLatest);
+
+                            if (String.IsNullOrEmpty(path))
+                            {
+                                Log.LogMessageFromResources(
+                                    MessageImportance.High,
+                                    "GetFrameworkSdkPath.CouldNotFindSDK",
+                                    ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Version40, VisualStudioVersion.VersionLatest),
+                                    ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Version40, VisualStudioVersion.VersionLatest));
+
+                                path = String.Empty;
+                            }
+                            else
+                            {
+                                path = FrameworkFileUtilities.EnsureTrailingSlash(path);
+                                Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", path);
+                            }
+                            
+                            s_version40Path = path;
+                        }
                     }
                 }
 
-                return s_version40Path;
+                return path;
             }
         }
 
@@ -175,28 +217,38 @@ public string FrameworkSdkVersion45Path
         {
             get
             {
-                if (s_version45Path == null)
+                string path = s_version45Path;
+                if (path == null)
                 {
-                    s_version45Path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Version45, VisualStudioVersion.VersionLatest);
-
-                    if (String.IsNullOrEmpty(s_version45Path))
-                    {
-                        Log.LogMessageFromResources(
-                            MessageImportance.High,
-                            "GetFrameworkSdkPath.CouldNotFindSDK",
-                            ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Version45, VisualStudioVersion.VersionLatest),
-                            ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Version45, VisualStudioVersion.VersionLatest));
-
-                        s_version45Path = String.Empty;
-                    }
-                    else
+                    lock (s_lockObject)
                     {
-                        s_version45Path = FrameworkFileUtilities.EnsureTrailingSlash(s_version45Path);
-                        Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", s_version45Path);
+                        path = s_version45Path;
+                        if (path == null)
+                        {
+                            path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Version45, VisualStudioVersion.VersionLatest);
+
+                            if (String.IsNullOrEmpty(path))
+                            {
+                                Log.LogMessageFromResources(
+                                    MessageImportance.High,
+                                    "GetFrameworkSdkPath.CouldNotFindSDK",
+                                    ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Version45, VisualStudioVersion.VersionLatest),
+                                    ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Version45, VisualStudioVersion.VersionLatest));
+
+                                path = String.Empty;
+                            }
+                            else
+                            {
+                                path = FrameworkFileUtilities.EnsureTrailingSlash(path);
+                                Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", path);
+                            }
+                            
+                            s_version45Path = path;
+                        }
                     }
                 }
 
-                return s_version45Path;
+                return path;
             }
         }
 
@@ -208,28 +260,38 @@ public string FrameworkSdkVersion451Path
         {
             get
             {
-                if (s_version451Path == null)
+                string path = s_version451Path;
+                if (path == null)
                 {
-                    s_version451Path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Version451, VisualStudioVersion.VersionLatest);
-
-                    if (String.IsNullOrEmpty(s_version451Path))
-                    {
-                        Log.LogMessageFromResources(
-                            MessageImportance.High,
-                            "GetFrameworkSdkPath.CouldNotFindSDK",
-                            ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Version451, VisualStudioVersion.VersionLatest),
-                            ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Version451, VisualStudioVersion.VersionLatest));
-
-                        s_version451Path = String.Empty;
-                    }
-                    else
+                    lock (s_lockObject)
                     {
-                        s_version451Path = FrameworkFileUtilities.EnsureTrailingSlash(s_version451Path);
-                        Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", s_version451Path);
+                        path = s_version451Path;
+                        if (path == null)
+                        {
+                            path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Version451, VisualStudioVersion.VersionLatest);
+
+                            if (String.IsNullOrEmpty(path))
+                            {
+                                Log.LogMessageFromResources(
+                                    MessageImportance.High,
+                                    "GetFrameworkSdkPath.CouldNotFindSDK",
+                                    ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Version451, VisualStudioVersion.VersionLatest),
+                                    ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Version451, VisualStudioVersion.VersionLatest));
+
+                                path = String.Empty;
+                            }
+                            else
+                            {
+                                path = FrameworkFileUtilities.EnsureTrailingSlash(path);
+                                Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", path);
+                            }
+                            
+                            s_version451Path = path;
+                        }
                     }
                 }
 
-                return s_version451Path;
+                return path;
             }
         }
 
@@ -241,28 +303,38 @@ public string FrameworkSdkVersion46Path
         {
             get
             {
-                if (s_version46Path == null)
+                string path = s_version46Path;
+                if (path == null)
                 {
-                    s_version46Path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Version46, VisualStudioVersion.VersionLatest);
-
-                    if (String.IsNullOrEmpty(s_version46Path))
-                    {
-                        Log.LogMessageFromResources(
-                            MessageImportance.High,
-                            "GetFrameworkSdkPath.CouldNotFindSDK",
-                            ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Version46, VisualStudioVersion.VersionLatest),
-                            ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Version46, VisualStudioVersion.VersionLatest));
-
-                        s_version46Path = String.Empty;
-                    }
-                    else
+                    lock (s_lockObject)
                     {
-                        s_version46Path = FrameworkFileUtilities.EnsureTrailingSlash(s_version46Path);
-                        Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", s_version46Path);
+                        path = s_version46Path;
+                        if (path == null)
+                        {
+                            path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Version46, VisualStudioVersion.VersionLatest);
+
+                            if (String.IsNullOrEmpty(path))
+                            {
+                                Log.LogMessageFromResources(
+                                    MessageImportance.High,
+                                    "GetFrameworkSdkPath.CouldNotFindSDK",
+                                    ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Version46, VisualStudioVersion.VersionLatest),
+                                    ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Version46, VisualStudioVersion.VersionLatest));
+
+                                path = String.Empty;
+                            }
+                            else
+                            {
+                                path = FrameworkFileUtilities.EnsureTrailingSlash(path);
+                                Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", path);
+                            }
+                            
+                            s_version46Path = path;
+                        }
                     }
                 }
 
-                return s_version46Path;
+                return path;
             }
         }
 
@@ -274,28 +346,38 @@ public string FrameworkSdkVersion461Path
         {
             get
             {
-                if (s_version461Path == null)
+                string path = s_version461Path;
+                if (path == null)
                 {
-                    s_version461Path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Version461, VisualStudioVersion.VersionLatest);
-
-                    if (String.IsNullOrEmpty(s_version461Path))
-                    {
-                        Log.LogMessageFromResources(
-                            MessageImportance.High,
-                            "GetFrameworkSdkPath.CouldNotFindSDK",
-                            ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Version461, VisualStudioVersion.VersionLatest),
-                            ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Version461, VisualStudioVersion.VersionLatest));
-
-                        s_version461Path = String.Empty;
-                    }
-                    else
+                    lock (s_lockObject)
                     {
-                        s_version461Path = FrameworkFileUtilities.EnsureTrailingSlash(s_version461Path);
-                        Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", s_version461Path);
+                        path = s_version461Path;
+                        if (path == null)
+                        {
+                            path = ToolLocationHelper.GetPathToDotNetFrameworkSdk(TargetDotNetFrameworkVersion.Version461, VisualStudioVersion.VersionLatest);
+
+                            if (String.IsNullOrEmpty(path))
+                            {
+                                Log.LogMessageFromResources(
+                                    MessageImportance.High,
+                                    "GetFrameworkSdkPath.CouldNotFindSDK",
+                                    ToolLocationHelper.GetDotNetFrameworkSdkInstallKeyValue(TargetDotNetFrameworkVersion.Version461, VisualStudioVersion.VersionLatest),
+                                    ToolLocationHelper.GetDotNetFrameworkSdkRootRegistryKey(TargetDotNetFrameworkVersion.Version461, VisualStudioVersion.VersionLatest));
+
+                                path = String.Empty;
+                            }
+                            else
+                            {
+                                path = FrameworkFileUtilities.EnsureTrailingSlash(path);
+                                Log.LogMessageFromResources(MessageImportance.Low, "GetFrameworkSdkPath.FoundSDK", path);
+                            }
+                            
+                            s_version461Path = path;
+                        }
                     }
                 }
 
-                return s_version461Path;
+                return path;
             }
         }
 
@@ -318,6 +400,7 @@ public override bool Execute()
     }
 #else
 
+    [MSBuildMultiThreadableTask]
     public sealed class GetFrameworkSdkPath : TaskRequiresFramework, IGetFrameworkSdkPathTaskContract
     {
         public GetFrameworkSdkPath()