diff --git a/src/LaunchDarkly.EventSource/Properties/AssemblyInfo.cs b/src/LaunchDarkly.EventSource/Properties/AssemblyInfo.cs
index 81d5660..21dee05 100644
--- a/src/LaunchDarkly.EventSource/Properties/AssemblyInfo.cs
+++ b/src/LaunchDarkly.EventSource/Properties/AssemblyInfo.cs
@@ -1,4 +1,6 @@
 using System.Runtime.CompilerServices;
 
+#if DEBUG
 // Added to allow the Test Project to access internal types and methods.
-[assembly: InternalsVisibleTo("LaunchDarkly.EventSource.Tests")]
\ No newline at end of file
+[assembly: InternalsVisibleTo("LaunchDarkly.EventSource.Tests")]
+#endif