diff --git a/sources/reactphysics3d/engine/NumericalIntegrator.cpp b/sources/reactphysics3d/engine/NumericalIntegrator.cpp
new file mode 100644
index 00000000..945f577a
--- /dev/null
+++ b/sources/reactphysics3d/engine/NumericalIntegrator.cpp
@@ -0,0 +1,55 @@
+/****************************************************************************
+* Copyright (C) 2009      Daniel Chappuis                                  *
+****************************************************************************
+* This file is part of ReactPhysics3D.                                     *
+*                                                                          *
+* ReactPhysics3D is free software: you can redistribute it and/or modify   *
+* it under the terms of the GNU General Public License as published by     *
+* the Free Software Foundation, either version 3 of the License, or        *
+* (at your option) any later version.                                      *
+*                                                                          *
+* ReactPhysics3D is distributed in the hope that it will be useful,        *
+* but WITHOUT ANY WARRANTY; without even the implied warranty of           *
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the             *
+* GNU General Public License for more details.                             *
+*                                                                          *
+* You should have received a copy of the GNU General Public License        *
+* along with ReactPhysics3D. If not, see <http://www.gnu.org/licenses/>.   *
+***************************************************************************/
+
+// Libraries
+#include "NumericalIntegrator.h"
+
+// We want to use the ReactPhysics3D namespace
+using namespace reactphysics3d;
+
+// Constructor
+NumericalIntegrator::NumericalIntegrator() {
+
+}
+
+// Copy-constructor
+NumericalIntegrator::NumericalIntegrator(const NumericalIntegrator& integrator) {
+
+}
+
+// Destructor
+NumericalIntegrator::~NumericalIntegrator() {
+
+}
+
+// Compute a derivative body state at time t+dt
+DerivativeBodyState NumericalIntegrator::evaluate(BodyState& bodyState, const Time& time, const Time& timeStep) {
+    // TODO : Implement this method
+}
+
+// Compute a derivative body state at time t + dt according to the last derivative body state
+DerivativeBodyState NumericalIntegrator::evaluate(BodyState& bodyState, const Time& time, const Time& timeStep,
+                                                  const BodyState& lastDerivativeBodyState) {
+    // TODO : Implement this method
+}
+
+// Integrate a body state over time
+void NumericalIntegrator::integrate(BodyState& bodyState, const Time& t, const Time& dt) {
+    // TODO : Implement this method
+}
diff --git a/sources/reactphysics3d/engine/NumericalIntegrator.h b/sources/reactphysics3d/engine/NumericalIntegrator.h
new file mode 100644
index 00000000..cc3f1205
--- /dev/null
+++ b/sources/reactphysics3d/engine/NumericalIntegrator.h
@@ -0,0 +1,53 @@
+/****************************************************************************
+* Copyright (C) 2009      Daniel Chappuis                                  *
+****************************************************************************
+* This file is part of ReactPhysics3D.                                     *
+*                                                                          *
+* ReactPhysics3D is free software: you can redistribute it and/or modify   *
+* it under the terms of the GNU General Public License as published by     *
+* the Free Software Foundation, either version 3 of the License, or        *
+* (at your option) any later version.                                      *
+*                                                                          *
+* ReactPhysics3D is distributed in the hope that it will be useful,        *
+* but WITHOUT ANY WARRANTY; without even the implied warranty of           *
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the             *
+* GNU General Public License for more details.                             *
+*                                                                          *
+* You should have received a copy of the GNU General Public License        *
+* along with ReactPhysics3D. If not, see <http://www.gnu.org/licenses/>.   *
+***************************************************************************/
+
+#ifndef NUMERICALINTEGRATOR_H
+#define NUMERICALINTEGRATOR_H
+
+// Libraries
+#include "../body/BodyState.h"
+#include "../body/DerivativeBodyState.h"
+
+// Namespace ReactPhysics3D
+namespace reactphysics3d {
+
+/*  -------------------------------------------------------------------
+    Class NumericalIntegrator :
+        This class will be used to solve the differential equation of
+        movement by integrating a body state. This integrator implements
+        the RK4 integrator.
+    -------------------------------------------------------------------
+*/
+class NumericalIntegrator {
+    private :
+        DerivativeBodyState evaluate(BodyState& bodyState, const Time& time, const Time& timeStep);     // Compute a derivative body state
+        DerivativeBodyState evaluate(BodyState& bodyState, const Time& time,
+                                     const Time& timeStep, const BodyState& lastDerivativeBodyState);   // Compute a derivative body state
+
+    public :
+        NumericalIntegrator();                                          // Constructor
+        NumericalIntegrator(const NumericalIntegrator& integrator);     // Copy-constructor
+        virtual ~NumericalIntegrator();                                 // Destructor
+
+        void integrate(BodyState& bodyState, const Time& t, const Time& dt);    // Integrate a body state over time
+}
+
+}
+
+#endif