diff --git a/dune/solvers/solvers/iterativesolver.cc b/dune/solvers/solvers/iterativesolver.cc
index 8aa5a6a2656ba18a4094ed3b9aaa640b86e5abcd..fdb64fe0132b70bb0c695e1f6247e7697a31f398 100644
--- a/dune/solvers/solvers/iterativesolver.cc
+++ b/dune/solvers/solvers/iterativesolver.cc
@@ -9,6 +9,9 @@
 
 #include <dune/matrix-vector/genericvectortools.hh>
 
+namespace Dune {
+namespace Solvers {
+
 template <class VectorType, class BitVectorType>
 void IterativeSolver<VectorType, BitVectorType>::check() const
 {
@@ -37,3 +40,6 @@ void IterativeSolver<VectorType, BitVectorType>::writeIterate(const VectorType&
 
     file.close();
 }
+
+} /* namespace Solvers */
+} /* namespace Dune */