diff --git a/trunk/paradiseo-peo/src/peoEvalFuncPSO.h b/trunk/paradiseo-peo/src/peoEvalFuncPSO.h
index d08515bd2..7f94974b8 100644
--- a/trunk/paradiseo-peo/src/peoEvalFuncPSO.h
+++ b/trunk/paradiseo-peo/src/peoEvalFuncPSO.h
@@ -1,4 +1,4 @@
-// "peoPSO.h"
+// "peoEvalFuncPSO.h"
 
 // (c) OPAC Team, October 2007
 
@@ -11,6 +11,11 @@
 
 #include <eoEvalFunc.h>
 
+/** peoEvalFuncPSO: This class
+ * takes an existing function pointer and converts it into a evaluation
+ * function class. 
+ */
+
 #ifdef _MSC_VER
 template< class POT, class FitT = POT::Fitness, class FunctionArg = const POT& >
 #else
@@ -21,6 +26,7 @@ struct peoEvalFuncPSO: public eoEvalFunc<POT> {
   peoEvalFuncPSO( FitT (* _eval)( FunctionArg ) )
     : eoEvalFunc<POT>(), evalFunc( _eval ) {};
   
+    //Applies the evaluation function to a PEO
   virtual void operator() ( POT & _peo ) 
   {
       _peo.fitness((*evalFunc)( _peo ));
diff --git a/trunk/paradiseo-peo/src/peoPSO.h b/trunk/paradiseo-peo/src/peoPSO.h
index 73b7b4a9f..83ef1154a 100644
--- a/trunk/paradiseo-peo/src/peoPSO.h
+++ b/trunk/paradiseo-peo/src/peoPSO.h
@@ -24,16 +24,19 @@ template < class POT > class peoPSO : public Runner {
 
 public:
 
+
+  // Constructor for the Particle Swarm Optimization
   peoPSO(
 	 eoContinue< POT >& __cont,
 	 peoPopEval< POT >& __pop_eval,
 	 eoVelocity < POT > &_velocity,
 	 eoFlight < POT > &_flight);
 
-
+  // Particle Swarm Optimization function - a side effect of the fact that the class is derived from the Runner class
+  // thus requiring the existence of a run function, the algorithm being executed on a distinct thread.
 	void run();
 	
-
+  // Function operator for specifying the population to be associated with the algorithm.
 	void operator()( eoPop< POT >& __pop );
 
 private: