diff --git a/Vonage.Test/ConfigurationTest.cs b/Vonage.Test/ConfigurationTest.cs
index 47f39629..3934016a 100644
--- a/Vonage.Test/ConfigurationTest.cs
+++ b/Vonage.Test/ConfigurationTest.cs
@@ -210,6 +210,7 @@ public void VonageUrl_ShouldReturnNexmoUrl() =>
 }
 
 [Trait("Category", "HttpConnectionPool")]
+[CollectionDefinition("HttpConnectionPool", DisableParallelization = true)]
 public class ConnectionLifetimeTest
 {
     private readonly ITestOutputHelper output;