diff --git a/htdocs/categories/class/categorie.class.php b/htdocs/categories/class/categorie.class.php
index ee4ff76a008..1e48d484406 100644
--- a/htdocs/categories/class/categorie.class.php
+++ b/htdocs/categories/class/categorie.class.php
@@ -28,6 +28,7 @@
 
 require_once DOL_DOCUMENT_ROOT.'/product/class/product.class.php';
 require_once DOL_DOCUMENT_ROOT.'/fourn/class/fournisseur.class.php';
+require_once DOL_DOCUMENT_ROOT.'/contact/class/contact.class.php';
 
 
 /**