diff --git a/emper/Common.hpp b/emper/Common.hpp
index 72136a72e4a0ed1ba867112f22f7549dd876cfa6..9dd9c61af99f85cfa2a9d1d370c9bc556f8f695d 100644
--- a/emper/Common.hpp
+++ b/emper/Common.hpp
@@ -3,6 +3,7 @@
 #pragma once
 
 #include <functional>
+#include <sstream>	// IWYU pragma: keep
 
 using func_t = std::function<void()>;