diff --git a/src/propertywatch.hpp b/src/propertywatch.hpp
index ecb8e9c..84b6af7 100644
--- a/src/propertywatch.hpp
+++ b/src/propertywatch.hpp
@@ -11,6 +11,8 @@
 #include "filters.hpp"
 #include "watch.hpp"
 
+#include <string>
+
 namespace phosphor
 {
 namespace dbus