diff --git a/csharp/.gitignore b/csharp/.gitignore
index 19af6f8..d7dcef5 100644
--- a/csharp/.gitignore
+++ b/csharp/.gitignore
@@ -6,6 +6,8 @@
 src/ProtocolBuffers/bin/
 src/ProtocolBuffers/obj/
 src/ProtocolBuffers/objCF
+src/ProtocolBuffers.Serialization/bin/
+src/ProtocolBuffers.Serialization/obj/
 src/ProtocolBuffers.Test/bin/
 src/ProtocolBuffers.Test/obj/
 src/ProtocolBuffersLite.Test/bin/