diff --git a/src/debugger/main.ts b/src/debugger/main.ts
index 03e82a6d9..774bcda55 100644
--- a/src/debugger/main.ts
+++ b/src/debugger/main.ts
@@ -293,42 +293,70 @@ class RubyDebugSession extends DebugSession {
         return localPath.replace(/\\/g, '/');
     }
 
+    private isSubPath(subPath: string): boolean {
+        return subPath && !subPath.startsWith('..') && !path.isAbsolute(subPath);
+    }
+
+    private getPathImplementation(pathToCheck: string): any {
+        if (pathToCheck) {
+            if (pathToCheck.indexOf(path.posix.sep) >= 0) {
+                return path.posix;
+            } else if (pathToCheck.indexOf(path.win32.sep) >= 0) {
+                return path.win32;
+            }
+        }
+
+        return path;
+    }
+
     protected convertClientPathToDebugger(localPath: string): string {
-        if (this.debugMode == Mode.launch) {
+        if (this.debugMode === Mode.launch) {
             return localPath;
         }
 
-        if (!localPath.startsWith(this.requestArguments.cwd)) {
+        let relativeLocalPath = path.relative(this.requestArguments.cwd, localPath);
+
+        if (!this.isSubPath(relativeLocalPath)) {
             return localPath;
         }
 
-        var relativePath = path.join(
-            this.requestArguments.remoteWorkspaceRoot, localPath.substring(this.requestArguments.cwd.length)
-        );
+        let remoteWorkspaceRoot =
+            this.requestArguments.remoteWorkspaceRoot || this.requestArguments.cwd;
 
-        var sepIndex = this.requestArguments.remoteWorkspaceRoot.lastIndexOf('/');
+        let remotePathImplementation = this.getPathImplementation(remoteWorkspaceRoot);
+        let localPathImplementation = this.getPathImplementation(this.requestArguments.cwd);
 
-        if (sepIndex !== -1) {
-            // *inx or darwin
-            relativePath = relativePath.replace(/\\/g, '/');
-        }
+        let relativePath = remotePathImplementation.join.apply(
+            null,
+            [remoteWorkspaceRoot].concat(relativeLocalPath.split(localPathImplementation.sep))
+        );
 
         return relativePath;
     }
 
-    protected convertDebuggerPathToClient(serverPath: string):string{
-        if (this.debugMode == Mode.launch) {
+    protected convertDebuggerPathToClient(serverPath: string): string {
+        if (this.debugMode === Mode.launch) {
             return serverPath;
         }
 
-        if (!serverPath.startsWith(this.requestArguments.remoteWorkspaceRoot)) {
+        let remoteWorkspaceRoot =
+            this.requestArguments.remoteWorkspaceRoot || this.requestArguments.cwd;
+
+        let remotePathImplementation = this.getPathImplementation(remoteWorkspaceRoot);
+        let localPathImplementation = this.getPathImplementation(this.requestArguments.cwd);
+
+        let relativeRemotePath = remotePathImplementation.relative(remoteWorkspaceRoot, serverPath);
+
+
+        if (!this.isSubPath(relativeRemotePath)) {
             return serverPath;
         }
 
-        // Path.join will convert the path using local OS preferred separator
-        var relativePath = path.join(
-            this.requestArguments.cwd, serverPath.substring(this.requestArguments.remoteWorkspaceRoot.length)
+        let relativePath = localPathImplementation.join.apply(
+            null,
+            [this.requestArguments.cwd].concat(relativeRemotePath.split(remotePathImplementation.sep))
         );
+
         return relativePath;
     }