diff --git a/eo/src/eo b/eo/src/eo
index 272dd4b6..3c6bd22c 100644
--- a/eo/src/eo
+++ b/eo/src/eo
@@ -177,6 +177,7 @@
 #include <eoTopology.h>
 #include <eoStarTopology.h>
 #include <eoLinearTopology.h>
+#include <eoRingTopology.h>
 #include <eoNeighborhood.h>  
 #include <eoSocialNeighborhood.h> 
   
diff --git a/eo/src/eoLinearTopology.h b/eo/src/eoLinearTopology.h
index 7eb68ec5..164d2bf4 100644
--- a/eo/src/eoLinearTopology.h
+++ b/eo/src/eoLinearTopology.h
@@ -1,4 +1,3 @@
-
 // -*- mode: c++; c-indent-level: 4; c++-member-init-indent: 8; comment-column: 35; -*-
 
 //-----------------------------------------------------------------------------
diff --git a/eo/src/eoRingTopology.h b/eo/src/eoRingTopology.h
new file mode 100644
index 00000000..0dff3147
--- /dev/null
+++ b/eo/src/eoRingTopology.h
@@ -0,0 +1,163 @@
+// -*- mode: c++; c-indent-level: 4; c++-member-init-indent: 8; comment-column: 35; -*-
+
+//-----------------------------------------------------------------------------
+// eoRingTopology.h
+// (c) INRIA Futurs DOLPHIN 2007
+/* 
+    Clive Canape
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2 of the License, or (at your option) any later version.
+
+    This library 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
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+    Contact: clive.canape@inria.fr
+ */
+//-----------------------------------------------------------------------------
+
+#ifndef EORINGTOPOLOGY_H_
+#define EORINGTOPOLOGY_H_
+
+//-----------------------------------------------------------------------------
+#include <eoTopology.h>
+#include <eoSocialNeighborhood.h>
+//-----------------------------------------------------------------------------
+
+
+/**
+ * Topology dedicated to "globest best" strategy for particle swarm optimization.
+ * All the particles of the swarm belong to the same and only social neighborhood.
+ * The global best is stored as a protected member and updated by using the "updateNeighborhood" method.
+ */
+template < class POT > class eoRingTopology:public eoTopology <POT>
+{
+
+public:
+
+    /**
+     * The only Ctor. No parameter required.
+     */
+    eoRingTopology (unsigned _neighborhoodSize):neighborhoodSize (_neighborhoodSize),isSetup(false){}
+
+
+    /**
+     * Builds the only neighborhood that contains all the particles of the given population.
+     * Also initializes the global best particle with the best particle of the given population.
+     * @param _pop - The population used to build the only neighborhood.
+     * @return
+     */
+    void setup(const eoPop<POT> & _pop)
+    {
+        if (!isSetup){
+
+            // put in the neighborhood
+            int k = neighborhoodSize/2;
+            for (unsigned i=0;i < _pop.size();i++)
+            {
+            	eoSocialNeighborhood<POT> currentNghd;
+            	currentNghd.best(_pop[i]);
+            	for (unsigned j=0; j < neighborhoodSize; j++)
+            	{
+               		currentNghd.put((_pop.size()+i-k+j)%_pop.size());
+            		if(_pop[(_pop.size()+i-k+j)%_pop.size()].fitness() > currentNghd.best().fitness())
+                        currentNghd.best(_pop[(_pop.size()+i-k+j)%_pop.size()]);
+                }
+            	neighborhood.push_back(currentNghd);
+            }	
+            isSetup=true;
+        }
+        else
+        {
+            // Should activate this part ?
+            /*
+               std::string s;
+               s.append (" Linear topology already setup in eoRingTopology");
+               throw std::runtime_error (s);
+               */
+        }
+    }
+    
+    /**
+     * Retrieve the neighboorhood of a particle.
+     * @return _indice - The particle indice (in the population)
+     */
+    unsigned retrieveNeighborhoodByIndice(unsigned _indice)
+    {
+        return _indice;
+    }
+
+
+    /**
+     * Update the best fitness of the given particle if it's better.
+     * Also replace the global best by the given particle if it's better.
+     * @param _po - The particle to update
+     * @param _indice - The indice of the given particle in the population
+     */
+    void updateNeighborhood(POT & _po,unsigned _indice)
+    {
+    	//this->printOn();exit(0);
+        // update the best fitness of the particle
+        if (_po.fitness() > _po.best())
+        {
+            _po.best(_po.fitness());
+            for(unsigned i=0;i<_po.size();i++)
+	    		_po.bestPositions[i]=_po[i];	
+        }
+        // update the global best if the given particle is "better"
+        for (unsigned i=-neighborhoodSize+1; i < neighborhoodSize; i++)
+            	{
+            		unsigned indi = (_po.size()+_indice+i)%_po.size();
+            		if (_po.fitness() > neighborhood[indi].best().fitness())
+            			neighborhood[indi].best(_po);
+                }
+     }
+
+
+    /**
+     * Return the global best particle.
+     * @param _indice - The indice of a particle in the population
+     * @return POT & - The best particle in the neighborhood of the particle whose indice is _indice
+     */
+    POT & best (unsigned  _indice) 
+    {
+    	unsigned theGoodNhbd= retrieveNeighborhoodByIndice(_indice);
+
+        return (neighborhood[theGoodNhbd].best());
+    }
+
+
+    /**
+     * Print the structure of the topology on the standard output.
+     * @param
+     * @return
+     */
+    void printOn()
+    {
+        for (unsigned i=0;i< neighborhood.size();i++)
+        {
+            std::cout << "{ " ;
+            for (unsigned j=0;j< neighborhood[i].size();j++)
+            {
+                std::cout << neighborhood[i].get(j) << " ";
+            }
+            std::cout << "}" << std::endl;
+        }
+    }
+
+
+protected:
+    std::vector<eoSocialNeighborhood<POT> >  neighborhood;
+    unsigned neighborhoodSize; 
+    bool isSetup;
+};
+
+#endif /*EORINGTOPOLOGY_H_*/