diff --git a/dune/gfe/globalgfetestfunctionbasis.hh b/dune/gfe/globalgfetestfunctionbasis.hh
index 5f61e6fcbb62d3444e666e431ff53172583d9b15..c466eeeb4d21493e138c1564a8e613b53745fab5 100644
--- a/dune/gfe/globalgfetestfunctionbasis.hh
+++ b/dune/gfe/globalgfetestfunctionbasis.hh
@@ -61,7 +61,7 @@ public:
     /** \brief Get the total number of global (block) basis functions.
      *  Only return the number of Lagrange points. For each Lagrange point there are (tangentDim) local shape functions
      */
-    int size() const
+    size_t size() const
     { 
         return basis_.size();
     }