diff --git a/boost/atomic/detail/generic-cas.hpp b/boost/atomic/detail/generic-cas.hpp
index 83b90ed..6622af5 100644
--- a/boost/atomic/detail/generic-cas.hpp
+++ b/boost/atomic/detail/generic-cas.hpp
@@ -40,7 +40,10 @@ each operation) */
 #elif defined(__ICL) || defined(_MSC_VER)
 
     #if defined(_MSC_VER)
-    #include <Windows.h>
+    // Include WinSock2.h instead of Windows.h to avoid pulling in
+    // Winsock 1.0 declarations.  WindSock2.h includes Windows.h, so
+    // separate include of Windows.h is not necessary.
+    #include <WinSock2.h>
     #include <intrin.h>
     #endif