diff --git a/src/Server.h b/src/Server.h
index 2f26b8aef7..215b7e930d 100644
--- a/src/Server.h
+++ b/src/Server.h
@@ -15,6 +15,7 @@
 #define SERVER_H
 
 #include <memory>
+#include <string>
 #include <vector>
 
 #ifdef _WIN32