diff --git a/Directory.Packages.props b/Directory.Packages.props
index 083d02b..871f908 100644
--- a/Directory.Packages.props
+++ b/Directory.Packages.props
@@ -9,7 +9,7 @@
     <PackageVersion Include="Microsoft.Xaml.Behaviors.Wpf" Version="1.1.135" />
     <PackageVersion Include="MSTest.TestAdapter" Version="3.6.4" />
     <PackageVersion Include="MSTest.TestFramework" Version="3.6.4" />
-    <PackageVersion Include="System.Collections.Immutable" Version="9.0.0" />
+    <PackageVersion Include="System.Collections.Immutable" Version="5.0.0" />
     <PackageVersion Include="System.ValueTuple" Version="4.5.0" />
   </ItemGroup>
 </Project>
\ No newline at end of file