diff --git a/global.json b/global.json
index edbc8a2e4..860b52da4 100644
--- a/global.json
+++ b/global.json
@@ -1,6 +1,6 @@
 {
   "sdk": {
-    "version": "7.0.202",
+    "version": "7.0.203",
     "rollForward": "latestMinor"
   }
 }
diff --git a/src/TestableIO.System.IO.Abstractions.TestingHelpers/MockDirectory.cs b/src/TestableIO.System.IO.Abstractions.TestingHelpers/MockDirectory.cs
index 490030718..a7d476955 100644
--- a/src/TestableIO.System.IO.Abstractions.TestingHelpers/MockDirectory.cs
+++ b/src/TestableIO.System.IO.Abstractions.TestingHelpers/MockDirectory.cs
@@ -110,7 +110,17 @@ public override IFileSystemInfo CreateSymbolicLink(string path, string pathToTar
         /// <inheritdoc />
         public override IDirectoryInfo CreateTempSubdirectory(string prefix = null)
         {
-            throw CommonExceptions.NotImplemented();
+            prefix ??= "";
+            string potentialTempDirectory;
+
+            // Perform directory name generation in a loop, just in case the randomly generated name already exists.
+            do
+            {
+                var randomDir = $"{prefix}{Path.GetRandomFileName()}";
+                potentialTempDirectory = Path.Combine(Path.GetTempPath(), randomDir);
+            } while (Exists(potentialTempDirectory));
+
+            return CreateDirectoryInternal(potentialTempDirectory);
         }
 #endif
 
diff --git a/tests/TestableIO.System.IO.Abstractions.TestingHelpers.Tests/MockDirectoryTests.cs b/tests/TestableIO.System.IO.Abstractions.TestingHelpers.Tests/MockDirectoryTests.cs
index 543553fef..6992b0a8d 100644
--- a/tests/TestableIO.System.IO.Abstractions.TestingHelpers.Tests/MockDirectoryTests.cs
+++ b/tests/TestableIO.System.IO.Abstractions.TestingHelpers.Tests/MockDirectoryTests.cs
@@ -813,6 +813,37 @@ public void MockDirectory_CreateDirectory_ShouldSucceedIfTryingToCreateUNCPathSh
             Assert.IsTrue(fileSystem.Directory.Exists(@"\\server\share\"));
         }
 
+#if FEATURE_CREATE_TEMP_SUBDIRECTORY
+        [Test]
+        public void MockDirectory_CreateTempSubdirectory_ShouldCreateSubdirectoryInTempDirectory()
+        {
+            // Arrange
+            var fileSystem = new MockFileSystem();
+
+            // Act
+            var result = fileSystem.Directory.CreateTempSubdirectory();
+
+            // Assert
+            Assert.IsTrue(fileSystem.Directory.Exists(result.FullName));
+            Assert.IsTrue(result.FullName.Contains(Path.GetTempPath()));
+        }
+
+        [Test]
+        public void MockDirectory_CreateTempSubdirectoryWithPrefix_ShouldCreateDirectoryWithGivenPrefixInTempDirectory()
+        {
+            // Arrange
+            var fileSystem = new MockFileSystem();
+
+            // Act
+            var result = fileSystem.Directory.CreateTempSubdirectory("foo-");
+
+            // Assert
+            Assert.IsTrue(fileSystem.Directory.Exists(result.FullName));
+            Assert.IsTrue(Path.GetFileName(result.FullName).StartsWith("foo-"));
+            Assert.IsTrue(result.FullName.Contains(Path.GetTempPath()));
+        }
+#endif
+
         [Test]
         public void MockDirectory_Delete_ShouldDeleteDirectory()
         {