diff --git a/opm/autodiff/BlackoilModel.hpp b/opm/autodiff/BlackoilModel.hpp
index ed90eb4d9..14c669ff9 100644
--- a/opm/autodiff/BlackoilModel.hpp
+++ b/opm/autodiff/BlackoilModel.hpp
@@ -68,10 +68,10 @@ namespace Opm {
                       const bool                              has_disgas,
                       const bool                              has_vapoil,
                       const bool                              terminal_output)
-                : Base(param, grid, fluid, geo, rock_comp_props, wells, linsolver,
-                       has_disgas, has_vapoil, terminal_output)
-            {
-            }
+            : Base(param, grid, fluid, geo, rock_comp_props, wells, linsolver,
+                   has_disgas, has_vapoil, terminal_output)
+        {
+        }
     };
 
 
@@ -81,8 +81,8 @@ namespace Opm {
     {
         typedef BlackoilState ReservoirState;
         typedef WellStateFullyImplicitBlackoil WellState;
-        typedef BlackoilModelBase< Grid, BlackoilModel<Grid> > Base;
         typedef BlackoilModelParameters ModelParameters;
+        typedef DefaultBlackoilSolutionState SolutionState;
     };
 
 } // namespace Opm
diff --git a/opm/autodiff/BlackoilModelBase.hpp b/opm/autodiff/BlackoilModelBase.hpp
index e282ecee7..067dc6e4f 100644
--- a/opm/autodiff/BlackoilModelBase.hpp
+++ b/opm/autodiff/BlackoilModelBase.hpp
@@ -33,7 +33,6 @@
 
 #include <array>
 
-struct UnstructuredGrid;
 struct Wells;
 
 namespace Opm {
@@ -42,8 +41,35 @@ namespace Opm {
     class DerivedGeology;
     class RockCompressibility;
     class NewtonIterationBlackoilInterface;
-    class BlackoilState;
-    class WellStateFullyImplicitBlackoil;
+
+
+    /// Struct for containing iteration variables.
+    struct DefaultBlackoilSolutionState
+    {
+        typedef AutoDiffBlock<double> ADB;
+        explicit DefaultBlackoilSolutionState(const int np)
+            : pressure  (    ADB::null())
+            , temperature(   ADB::null())
+            , saturation(np, ADB::null())
+            , rs        (    ADB::null())
+            , rv        (    ADB::null())
+            , qs        (    ADB::null())
+            , bhp       (    ADB::null())
+            , canonical_phase_pressures(3, ADB::null())
+        {
+        }
+        ADB              pressure;
+        ADB              temperature;
+        std::vector<ADB> saturation;
+        ADB              rs;
+        ADB              rv;
+        ADB              qs;
+        ADB              bhp;
+        // Below are quantities stored in the state for optimization purposes.
+        std::vector<ADB> canonical_phase_pressures; // Always has 3 elements, even if only 2 phases active.
+    };
+
+
 
 
     /// Traits to encapsulate the types used by classes using or
@@ -76,6 +102,7 @@ namespace Opm {
         typedef typename ModelTraits<Implementation>::ReservoirState ReservoirState;
         typedef typename ModelTraits<Implementation>::WellState WellState;
         typedef typename ModelTraits<Implementation>::ModelParameters ModelParameters;
+        typedef typename ModelTraits<Implementation>::SolutionState SolutionState;
 
         // ---------  Public methods  ---------
 
@@ -192,19 +219,6 @@ namespace Opm {
             ADB              mob;   // Phase mobility (per cell)
         };
 
-        struct SolutionState {
-            SolutionState(const int np);
-            ADB              pressure;
-            ADB              temperature;
-            std::vector<ADB> saturation;
-            ADB              rs;
-            ADB              rv;
-            ADB              qs;
-            ADB              bhp;
-            // Below are quantities stored in the state for optimization purposes.
-            std::vector<ADB> canonical_phase_pressures; // Always has 3 elements, even if only 2 phases active.
-        };
-
         struct WellOps {
             WellOps(const Wells* wells);
             M w2p;              // well -> perf (scatter)
diff --git a/opm/autodiff/BlackoilModelBase_impl.hpp b/opm/autodiff/BlackoilModelBase_impl.hpp
index e1ac6e7bf..45f5d63f6 100644
--- a/opm/autodiff/BlackoilModelBase_impl.hpp
+++ b/opm/autodiff/BlackoilModelBase_impl.hpp
@@ -294,23 +294,6 @@ namespace detail {
 
 
 
-    template <class Grid, class Implementation>
-    BlackoilModelBase<Grid, Implementation>::SolutionState::SolutionState(const int np)
-        : pressure  (    ADB::null())
-        , temperature(   ADB::null())
-        , saturation(np, ADB::null())
-        , rs        (    ADB::null())
-        , rv        (    ADB::null())
-        , qs        (    ADB::null())
-        , bhp       (    ADB::null())
-        , canonical_phase_pressures(3, ADB::null())
-    {
-    }
-
-
-
-
-
     template <class Grid, class Implementation>
     BlackoilModelBase<Grid, Implementation>::
     WellOps::WellOps(const Wells* wells)