diff --git a/ixwebsocket/IXSocket.h b/ixwebsocket/IXSocket.h
index 9511dc87..68a5ac42 100644
--- a/ixwebsocket/IXSocket.h
+++ b/ixwebsocket/IXSocket.h
@@ -11,6 +11,7 @@
 #include <mutex>
 #include <atomic>
 #include <vector>
+#include <memory>
 
 #ifdef _WIN32
 #include <BaseTsd.h>