diff --git a/ImpesTPFAAD.hpp b/ImpesTPFAAD.hpp
index 18b9c8ad7..a76054e5b 100644
--- a/ImpesTPFAAD.hpp
+++ b/ImpesTPFAAD.hpp
@@ -27,6 +27,7 @@
 #include <opm/core/simulator/WellState.hpp>
 
 #include <algorithm>
+#include <cassert>
 #include <vector>
 
 #include <boost/shared_ptr.hpp>