diff --git a/eo/src/eoCombinedInit.h b/eo/src/eoCombinedInit.h
index 3d2441322..7acbe3795 100644
--- a/eo/src/eoCombinedInit.h
+++ b/eo/src/eoCombinedInit.h
@@ -53,7 +53,7 @@ public:
     rates.push_back(_rate);
     // compute the relative rates in percent - to warn the user!
     if (_verbose)
-      printOn(std::cout);
+      printOn( eo::log << eo::logging );
   }
 
   /** outputs the operators and percentages */
diff --git a/eo/src/eoDetTournamentSelect.h b/eo/src/eoDetTournamentSelect.h
index 4a197b3ab..7042a3394 100644
--- a/eo/src/eoDetTournamentSelect.h
+++ b/eo/src/eoDetTournamentSelect.h
@@ -33,6 +33,7 @@
 
 #include <eoFunctor.h>
 #include <eoPop.h>
+#include <utils/eoLogger.h>
 #include <utils/selectors.h>
 
 //-----------------------------------------------------------------------------
@@ -50,7 +51,7 @@ template <class EOT> class eoDetTournamentSelect: public eoSelectOne<EOT>
   eoDetTournamentSelect(unsigned _tSize = 2 ):eoSelectOne<EOT>(), tSize(_tSize) {
     // consistency check
     if (tSize < 2) {
-      std::cout << "Warning, Tournament size should be >= 2\nAdjusted to 2\n";
+        eo::log << eo::warnings << "Tournament size should be >= 2, adjusted to 2" << std::endl;
       tSize = 2;
     }
   }
diff --git a/eo/src/eoEvalContinue.h b/eo/src/eoEvalContinue.h
index 7ee38dee0..c8af79fe3 100644
--- a/eo/src/eoEvalContinue.h
+++ b/eo/src/eoEvalContinue.h
@@ -46,7 +46,7 @@ public:
       (void)_vEO;
     if (eval.value() >= repTotalEvaluations) 
       {
-	std::cout << "STOP in eoEvalContinue: Reached maximum number of evaluations [" << repTotalEvaluations << "]\n";
+          eo::log << eo::progress << "STOP in eoEvalContinue: Reached maximum number of evaluations [" << repTotalEvaluations << "]" << std::endl;
 	return false;
       }
     return true;
diff --git a/eo/src/eoGenContinue.h b/eo/src/eoGenContinue.h
index c578fcc9c..e670cf317 100644
--- a/eo/src/eoGenContinue.h
+++ b/eo/src/eoGenContinue.h
@@ -57,7 +57,7 @@ public:
       (void)_vEO;
     thisGeneration++;
     value() = thisGeneration;
-    //	  std::cout << " [" << thisGeneration << "] ";
+    
     if (thisGeneration >= repTotalGenerations) 
       {
 	  if (verbose)
diff --git a/eo/src/eoMGGReplacement.h b/eo/src/eoMGGReplacement.h
index c436f4ce3..55eaaa54b 100644
--- a/eo/src/eoMGGReplacement.h
+++ b/eo/src/eoMGGReplacement.h
@@ -58,7 +58,7 @@ public:
   {
     if (tSize < 2)
       { 
-	std::cout << "Warning, Size for eoDetTournamentTruncateSplit adjusted to 2\n";
+          eo::log << eo::warnings << "Warning, Size for eoDetTournamentTruncateSplit adjusted to 2" << std::endl;
 	tSize = 2;
       }
   }
diff --git a/eo/src/eoMerge.h b/eo/src/eoMerge.h
index defd1fc56..0e359ae53 100644
--- a/eo/src/eoMerge.h
+++ b/eo/src/eoMerge.h
@@ -70,7 +70,7 @@ public :
 	  throw std::logic_error("Negative number of offspring in eoElitism!");
 	combien = (unsigned int)_rate;
 	if (combien != _rate)
-	  std::cout << "Warning: Number of guys to merge in eoElitism was rounded";
+	  eo::log << eo::warnings << "Warning: Number of guys to merge in eoElitism was rounded" << std::endl;
       }
   }
   
diff --git a/eo/src/eoProportionalCombinedOp.h b/eo/src/eoProportionalCombinedOp.h
index e1f3053c7..79b74111d 100644
--- a/eo/src/eoProportionalCombinedOp.h
+++ b/eo/src/eoProportionalCombinedOp.h
@@ -29,6 +29,7 @@
 #include <eoFunctor.h>
 #include <eoOp.h>
 #include <utils/eoRNG.h>
+#include <utils/eoLogger.h>
 /**
 \defgroup PropCombinedOperators
 Combination of same-type Genetic Operators - Proportional choice
@@ -73,7 +74,7 @@ public:
     rates.push_back(_rate);
     // compute the relative rates in percent - to warn the user!
     if (_verbose)
-      printOn(std::cout);
+      printOn( eo::log << eo::logging );
   }
 
   // outputs the operators and percentages
@@ -129,9 +130,9 @@ virtual void add(eoBinOp<EOT> & _op, const double _rate, bool _verbose=false)
 	unsigned i;
 	for (i=0; i<ops.size(); i++)
 	  total += rates[i];
-	std::cout << "In " << className() << "\n" ;
+    eo::log << eo::logging << "In " << className() << std::endl ;
 	for (i=0; i<ops.size(); i++)
-	  std::cout << ops[i]->className() << " with rate " << 100*rates[i]/total << " %\n";
+	  eo::log << eo::logging << ops[i]->className() << " with rate " << 100*rates[i]/total << " %" << std::endl;
       }
   }
 
@@ -179,7 +180,7 @@ virtual void add(eoQuadOp<EOT> & _op, const double _rate, bool _verbose=false)
     rates.push_back(_rate);
     // compute the relative rates in percent - to warn the user!
     if (_verbose)
-      printOn(std::cout);
+      printOn( eo::log << eo::logging );
   }
 
   // outputs the operators and percentages
diff --git a/eo/src/eoReduce.h b/eo/src/eoReduce.h
index 31ecd7767..9d5ff97b4 100644
--- a/eo/src/eoReduce.h
+++ b/eo/src/eoReduce.h
@@ -90,7 +90,7 @@ typedef typename EOT::Fitness Fitness;
   {
     if (t_size < 2)
       { 
-	std::cout << "Warning: EP tournament size should be >= 2. Adjusted" << std::endl;
+          eo::log << eo::warnings << "Warning: EP tournament size should be >= 2. Adjusted" << std::endl;
 	t_size = 2;
       }
   }
@@ -193,7 +193,7 @@ public:
   {
     if (t_size < 2)
       { 
-	std::cout << "Warning, Size for eoDetTournamentTruncate adjusted to 2\n";
+          eo::log << eo::warnings << "Warning, Size for eoDetTournamentTruncate adjusted to 2" << std::endl;
 	t_size = 2;
       }
   }
@@ -241,12 +241,12 @@ public:
   {
     if (t_rate <= 0.5)
       { 
-	std::cout << "Warning, Rate for eoStochTournamentTruncate adjusted to 0.51\n";
+          eo::log << eo::warnings << "Warning, Rate for eoStochTournamentTruncate adjusted to 0.51" << std::endl;
 	t_rate = 0.51;
       }
     if (t_rate > 1)
       {
-	std::cout << "Warning, Rate for eoStochTournamentTruncate adjusted to 1\n";
+          eo::log << eo::warnings << "Warning, Rate for eoStochTournamentTruncate adjusted to 1" << std::endl;
 	t_rate = 1;
       }
   }
diff --git a/eo/src/eoReduceSplit.h b/eo/src/eoReduceSplit.h
index 62a6f142f..915de4741 100644
--- a/eo/src/eoReduceSplit.h
+++ b/eo/src/eoReduceSplit.h
@@ -215,7 +215,7 @@ public:
   {
     if (t_size < 2)
       { 
-	std::cout << "Warning, Size for eoDetTournamentTruncateSplit adjusted to 2\n";
+          eo::log << eo::warnings << "Warning, Size for eoDetTournamentTruncateSplit adjusted to 2" << std::endl;
 	t_size = 2;
       }
   }
@@ -266,12 +266,12 @@ public:
   {
     if (t_rate <= 0.5)
       { 
-	std::cout << "Warning, Rate for eoStochTournamentTruncateSplit adjusted to 0.51\n";
+          eo::log << eo:warnings << "Warning, Rate for eoStochTournamentTruncateSplit adjusted to 0.51" << std::endl;
 	t_rate = 0.51;
       }
     if (t_rate > 1)
       {
-	std::cout << "Warning, Rate for eoStochTournamentTruncateSplit adjusted to 1\n";
+          eo::log << eo::warnings << "Warning, Rate for eoStochTournamentTruncateSplit adjusted to 1" << std::endl;
 	t_rate = 1;
       }
   }
diff --git a/eo/src/eoVariableLengthCrossover.h b/eo/src/eoVariableLengthCrossover.h
index 1e0772da8..ff86c60f6 100644
--- a/eo/src/eoVariableLengthCrossover.h
+++ b/eo/src/eoVariableLengthCrossover.h
@@ -128,7 +128,7 @@ public :
 	      && (index<10000) );
     if (index >= 10000)
       {
-	std::cout << "Warning: impossible to generate individual of the right size in 10000 trials\n";
+          eo::log << eo::warnings << "Warning: impossible to generate individual of the right size in 10000 trials" << std::endl;
 	return false;
       }
   // here we know we have the right sizes: do the actual exchange
@@ -251,9 +251,10 @@ public :
     } while ( ( (tmp1.size()<Min) || (tmp2.size()<Min) ||
 	      (tmp1.size()>Max) || (tmp2.size()>Max) )
 	      && (index<10000) );
+    // FIXME bad hardcoded limit, should use an algorithm that guarantee a correct size in a finite number of tries
     if (index >= 10000)
       {
-	std::cout << "Warning: impossible to generate individual of the right size in 10000 trials\n";
+          eo::log << eo::warnings << "Warning: impossible to generate individual of the right size in 10000 trials" << std::endl;
 	return false;
       }
 
@@ -318,10 +319,10 @@ public :
       index++;
     } while ( ( (tmp1.size()<Min) || (tmp1.size()>Max) )
 	      && (index<10000) );
-    // this while condition is not optimal, as it may take some time
+    // this while condition is not optimal, as it may take some time, see the FIXME above
     if (index >= 10000)
       {
-	std::cout << "Warning: impossible to generate individual of the right size in 10000 trials\n";
+          eo::log << eo::warnings << "Warning: impossible to generate individual of the right size in 10000 trials" << std::endl;
 	return false;
       }
 
diff --git a/eo/src/eoVector.h b/eo/src/eoVector.h
index a3a634531..ce85391f6 100644
--- a/eo/src/eoVector.h
+++ b/eo/src/eoVector.h
@@ -26,6 +26,7 @@ Old contact: todos@geneura.ugr.es, http://geneura.ugr.es
 #include <vector>
 #include <iterator>
 #include <EO.h>
+#include <utils/eoLogger.h>
 
 /** Base class for fixed length chromosomes
 
@@ -71,7 +72,7 @@ public:
             if (_v.size() != size())	   // safety check
             {
                 if (size())		   // NOT an initial empty std::vector
-                    std::cout << "Warning: Changing size in eoVector assignation"<<std::endl;
+                    eo::log << eo::warnings << "Warning: Changing size in eoVector assignation" << std::endl;
                 resize(_v.size());
             }
 
diff --git a/eo/src/eoVectorParticle.h b/eo/src/eoVectorParticle.h
index ecb80a2ea..5143463d1 100644
--- a/eo/src/eoVectorParticle.h
+++ b/eo/src/eoVectorParticle.h
@@ -78,8 +78,7 @@ public:
         if (_v.size () != size ())	// safety check
         {
             if (size ())		// NOT an initial empty std::vector
-                std::
-                cout <<
+                eo::log << eo::warnings <<
                 "Warning: Changing position size in eoVectorParticle assignation"
                 << std::endl;
             resize (_v.size ());