diff --git a/src/tier1/utlbuffer.cpp b/src/tier1/utlbuffer.cpp
index 0286327d..00dfd58c 100644
--- a/src/tier1/utlbuffer.cpp
+++ b/src/tier1/utlbuffer.cpp
@@ -17,6 +17,7 @@
 // memdbgon must be the last include file in a .cpp file!!!
 #include "tier0/memdbgon.h"
 			    
+BEGIN_TIER1_NAMESPACE
 
 //-----------------------------------------------------------------------------
 // Character conversions for C strings
@@ -1806,4 +1807,6 @@ double CUtlBuffer::GetDouble()
 	double d;
 	GET_TYPE( double, d, "%f" );
 	return d;
-}
\ No newline at end of file
+}
+
+END_TIER1_NAMESPACE