diff --git a/src/IceUtils.h b/src/IceUtils.h
index 493661c..50a115b 100644
--- a/src/IceUtils.h
+++ b/src/IceUtils.h
@@ -15,6 +15,7 @@
 #define SUBZERO_SRC_ICEUTILS_H
 
 #include <climits>
+#include <mutex>
 
 namespace Ice {