diff --git a/Model/ClassVisitor.php b/Model/ClassVisitor.php
index ae2e925a4d15e0913fbf27336b3105e834c1cdc0..e559f0d3e2abcc875469c4916da19607f90ec31a 100644
--- a/Model/ClassVisitor.php
+++ b/Model/ClassVisitor.php
@@ -8,6 +8,8 @@
 
 namespace Irstea\PlantUmlBundle\Model;
 
+use Irstea\PlantUmlBundle\Model\Filter\AcceptAllFilter;
+use Irstea\PlantUmlBundle\Model\Namespace_\RootNamespace;
 use Irstea\PlantUmlBundle\Model\Node\Class_;
 use Irstea\PlantUmlBundle\Model\Node\Interface_;
 use Irstea\PlantUmlBundle\Model\Node\Trait_;
@@ -36,11 +38,11 @@ class ClassVisitor implements ClassVisitorInterface, WritableInterface
     public function __construct(ClassFilterInterface $filter = null)
     {
         $this->rootNamespace = new RootNamespace();
-        $this->filter = $filter ?: Filter\AcceptAllFilter::instance();
+        $this->filter = $filter ?: AcceptAllFilter::instance();
     }
 
     /**
-     * @param \Irstea\PlantUmlBundle\Model\ClassFilterInterface $filter
+     * @param ClassFilterInterface $filter
      * @return self
      */
     public function setClassFilter(ClassFilterInterface $filter)
diff --git a/Model/AbstractNamespace.php b/Model/Namespace_/AbstractNamespace.php
similarity index 93%
rename from Model/AbstractNamespace.php
rename to Model/Namespace_/AbstractNamespace.php
index 5cc0538ed707f8082ff3136b6589cf6917f40391..f2826c043f58447cb6794c05880fd089218a3b0a 100644
--- a/Model/AbstractNamespace.php
+++ b/Model/Namespace_/AbstractNamespace.php
@@ -6,8 +6,10 @@
  * Tous droits réservés.
  */
 
-namespace Irstea\PlantUmlBundle\Model;
+namespace Irstea\PlantUmlBundle\Model\Namespace_;
 
+use Irstea\PlantUmlBundle\Model\NamespaceInterface;
+use Irstea\PlantUmlBundle\Model\NodeInterface;
 use Irstea\PlantUmlBundle\Writer\WritableInterface;
 use Irstea\PlantUmlBundle\Writer\WriterInterface;
 
diff --git a/Model/Namespace_.php b/Model/Namespace_/Namespace_.php
similarity index 89%
rename from Model/Namespace_.php
rename to Model/Namespace_/Namespace_.php
index 0b504cafe34cd91046b7e73d0cd20c6dfc21c563..2f4977acfee00472aefd0811956bf54e99697173 100644
--- a/Model/Namespace_.php
+++ b/Model/Namespace_/Namespace_.php
@@ -6,8 +6,10 @@
  * Tous droits réservés.
  */
 
-namespace Irstea\PlantUmlBundle\Model;
+namespace Irstea\PlantUmlBundle\Model\Namespace_;
 
+use Irstea\PlantUmlBundle\Model\ArrowInterface;
+use Irstea\PlantUmlBundle\Model\NamespaceInterface;
 use Irstea\PlantUmlBundle\Writer\WriterInterface;
 
 /**
diff --git a/Model/RootNamespace.php b/Model/Namespace_/RootNamespace.php
similarity index 90%
rename from Model/RootNamespace.php
rename to Model/Namespace_/RootNamespace.php
index efa9f3df785d9d7cf02bc405f12e557543c5d565..52719daabac863ae1e2c2e83653cbcd0d73b44eb 100644
--- a/Model/RootNamespace.php
+++ b/Model/Namespace_/RootNamespace.php
@@ -6,8 +6,9 @@
  * Tous droits réservés.
  */
 
-namespace Irstea\PlantUmlBundle\Model;
+namespace Irstea\PlantUmlBundle\Model\Namespace_;
 
+use Irstea\PlantUmlBundle\Model\ArrowInterface;
 use Irstea\PlantUmlBundle\Writer\WriterInterface;
 
 /**