diff --git a/admin-dev/themes/default/template/controllers/categories/list_header.tpl b/admin-dev/themes/default/template/controllers/categories/list_header.tpl
index 1ceeefcd8..845c4ac0a 100644
--- a/admin-dev/themes/default/template/controllers/categories/list_header.tpl
+++ b/admin-dev/themes/default/template/controllers/categories/list_header.tpl
@@ -28,27 +28,20 @@
 
 {block name=leadin}
 <div class="cat_bar2">
-	{if count($categories_tree) == 0}
-		{if $category_root->id_category == 0}
-			&nbsp;<img src="../img/admin/home.gif" alt="" /> {$category_root->name}
+	{assign var=i value=0}
+	{foreach $categories_tree key=key item=category}
+		{if $i++ == 0}
+			&nbsp;<img src="../img/admin/home.gif" alt="" />
+			{assign var=params_url value=""}
 		{else}
-			&nbsp;<img src="../img/admin/home.gif" alt="" /> {$categories_name}
+			{assign var=params_url value="&id_category={$category.id_category}&viewcategory"}
 		{/if}
-	{else}
-		{if $category_root->id_category == 0}
-			&nbsp;<a href="{$currentIndex}&token={$token}"><img src="../img/admin/home.gif" alt="" /> {$category_root->name}</a>&nbsp;>&nbsp;
+		{if $key == 0}
+			{$category.name}
 		{else}
-			&nbsp;<a href="{$currentIndex}&id_category={$category_root->id_category}&token={$token}"><img src="../img/admin/home.gif" alt="" /> {$category_root->name}</a>&nbsp;>&nbsp;
+			<a href="{$currentIndex}{$params_url}&token={$token}">{$category.name}</a>&nbsp;>&nbsp;
 		{/if}
-
-		{foreach $categories_tree key=key item=category}
-			{if $key == 0}
-				{$category.name}
-			{else}
-				<a href="{$currentIndex}&token={$token}&id_category={$category.id_category}&viewcategory">{$category.name}</a>&nbsp;>&nbsp;
-			{/if}
-		{/foreach}
-	{/if}
+	{/foreach}
 </div>
 	{if isset($delete_category) && $delete_category}
 		<form action="{$REQUEST_URI}" method="post">
diff --git a/classes/Category.php b/classes/Category.php
index fd9aa872b..6d8a77ff2 100644
--- a/classes/Category.php
+++ b/classes/Category.php
@@ -390,19 +390,21 @@ class CategoryCore extends ObjectModel
 	  */
 	public static function regenerateEntireNtree()
 	{
-		$categories = Db::getInstance()->executeS('SELECT id_category, id_parent FROM '._DB_PREFIX_.'category ORDER BY id_category ASC');
+		$categories = Db::getInstance()->executeS('SELECT id_category, id_parent FROM '._DB_PREFIX_.'category ORDER BY id_parent, position ASC');
 		$categories_array = array();
 		foreach ($categories as $category)
-			$categories_array[(int)$category['id_parent']]['subcategories'][(int)$category['id_category']] = 1;
-			$n = 1;
-		Category::_subTree($categories_array, 1, $n);
+			$categories_array[$category['id_parent']]['subcategories'][] = $category['id_category'];
+		$n = 1;
+
+		if (isset($categories_array[0]) && $categories_array[0]['subcategories'])
+			Category::_subTree($categories_array, $categories_array[0]['subcategories'][0], $n);
 	}
 
 	protected static function _subTree(&$categories, $id_category, &$n)
 	{
-		$left = (int)$n++;
+		$left = $n++;
 		if (isset($categories[(int)$id_category]['subcategories']))
-			foreach (array_keys($categories[(int)$id_category]['subcategories']) as $id_subcategory)
+			foreach ($categories[(int)$id_category]['subcategories'] as $id_subcategory)
 				Category::_subTree($categories, (int)$id_subcategory, $n);
 		$right = (int)$n++;
 
@@ -660,7 +662,7 @@ class CategoryCore extends ObjectModel
 	  */
 	public static function getHomeCategories($id_lang, $active = true)
 	{
-		return Category::getChildren(1, $id_lang, $active);
+		return self::getChildren(1, $id_lang, $active);
 	}
 
 	public static function getRootCategory($id_lang = null, Shop $shop = null)
@@ -671,17 +673,13 @@ class CategoryCore extends ObjectModel
 		if (!$shop)
 			$shop = $context->shop;
 
-		// context : no multishop
-		if (count(Shop::getShops()) == 1)
-			if (count(Category::getCategoriesWithoutParent()) > 1)
-				$category = new Category();
-			else
-				$category = new Category($shop->getCategory(), $id_lang);
-		else // context : multishop
-			if (count(Category::getCategoriesWithoutParent()) > 1 && $context->shop() != Shop::CONTEXT_SHOP)
-				$category = new Category();
-			else
-				$category = new Category($shop->getCategory(), $id_lang);
+		$is_more_than_one_root_category = count(Category::getCategoriesWithoutParent()) > 1;
+		if ((!Shop::isFeatureActive() && $is_more_than_one_root_category) ||
+			Shop::isFeatureActive() && $is_more_than_one_root_category && $context->shop() != Shop::CONTEXT_SHOP)
+			$category = Category::getTopCategory();
+		else
+			$category = new Category($shop->getCategory(), $id_lang);
+
 		return $category;
 	}
 
@@ -932,17 +930,20 @@ class CategoryCore extends ObjectModel
 			LEFT JOIN `'._DB_PREFIX_.'category_lang` cl
 				ON (c.`id_category` = cl.`id_category`
 				AND `id_lang` = '.(int)$id_lang.$context->shop->addSqlRestrictionOnLang('cl').')';
-			if (count(Shop::getShops()) > 1 && $context->shop() == Shop::CONTEXT_SHOP)
+			if (Shop::isFeatureActive() && $context->shop() == Shop::CONTEXT_SHOP)
 				$sql .= '
 			LEFT JOIN `'._DB_PREFIX_.'category_shop` cs
 				ON c.`id_category` = cs.`id_category`';
 			$sql .= '
 			WHERE c.`id_category` = '.(int)$id_current;
-			if (count(Shop::getShops()) > 1 && $context->shop() == Shop::CONTEXT_SHOP)
+			if (Shop::isFeatureActive() && $context->shop() == Shop::CONTEXT_SHOP)
 				$sql .= '
 				AND cs.`id_shop` = '.(int)$context->shop->getID(true);
 			$root_category = Category::getRootCategory();
-			if ($context->shop() == Shop::CONTEXT_SHOP && (!Tools::isSubmit('id_category') || (int)Tools::getValue('id_category') == (int)$root_category->id_category || (int)$root_category->id_category == (int)$context->shop->id_category))
+			if (Shop::isFeatureActive() && $context->shop() == Shop::CONTEXT_SHOP &&
+				(!Tools::isSubmit('id_category') ||
+					(int)Tools::getValue('id_category') == (int)$root_category->id_category ||
+					(int)$root_category->id_category == (int)$context->shop->id_category))
 				$sql .= '
 					AND c.`id_parent` != 0';
 
@@ -952,7 +953,7 @@ class CategoryCore extends ObjectModel
 				$categories[] = $result[0];
 			else if (!$categories)
 				$categories = array();
-			if (!$result || $result[0]['id_category'] == $context->shop->id_category)
+			if (!$result || ($result[0]['id_category'] == $context->shop->id_category && Shop::isFeatureActive()))
 				return $categories;
 			$id_current = $result[0]['id_parent'];
 		}
@@ -1317,7 +1318,7 @@ class CategoryCore extends ObjectModel
 		SELECT DISTINCT c.*
 		FROM `'._DB_PREFIX_.'category` c
 		LEFT JOIN `'._DB_PREFIX_.'category_lang` cl ON (c.`id_category` = cl.`id_category` AND cl.`id_lang` = '.(int)Context::getContext()->language->id.')
-		WHERE `id_parent` = 0
+		WHERE `level_depth` = 1
 		');
 	}
 
@@ -1328,5 +1329,14 @@ class CategoryCore extends ObjectModel
 		FROM `'._DB_PREFIX_.'shop`
 		WHERE `id_category` = '.(int)$this->id);
 	}
-}
 
+	public static function getTopCategory()
+	{
+		$id_category = Db::getInstance()->getValue('
+		SELECT `id_category`
+		FROM `'._DB_PREFIX_.'category`
+		WHERE `id_parent` = 0
+		');
+		return new Category($id_category);
+	}
+}
diff --git a/classes/Tools.php b/classes/Tools.php
index 0293a0cba..dbc80d7a1 100644
--- a/classes/Tools.php
+++ b/classes/Tools.php
@@ -973,7 +973,9 @@ class ToolsCore
 		if ($categoryType === 'products')
 		{
 			$interval = Category::getInterval($id_category);
-			$intervalRoot = Category::getInterval($context->shop->getCategory());
+			$id_root_category = $context->shop->getCategory();
+			$root_category = new Category($id_root_category);
+			$intervalRoot = Category::getInterval($id_root_category);
 			if ($interval)
 			{
 				$sql = 'SELECT c.id_category, cl.name, cl.link_rewrite
@@ -985,6 +987,7 @@ class ToolsCore
 							AND c.nright <= '.$intervalRoot['nright'].'
 							AND cl.id_lang = '.(int)$context->language->id.'
 							AND c.active = 1
+							AND c.level_depth > '.(int)$root_category->level_depth.'
 						ORDER BY c.level_depth ASC';
 				$categories = Db::getInstance()->executeS($sql);
 
diff --git a/controllers/admin/AdminCategoriesController.php b/controllers/admin/AdminCategoriesController.php
index 7b071a189..d73d306d1 100644
--- a/controllers/admin/AdminCategoriesController.php
+++ b/controllers/admin/AdminCategoriesController.php
@@ -93,7 +93,10 @@ class AdminCategoriesControllerCore extends AdminController
 		if (($id_category = Tools::getvalue('id_category')) && $this->action != 'select_delete')
 			$this->_category = new Category($id_category);
 		else
-			$this->_category = new Category($this->context->shop->id_category);
+			if (Shop::isFeatureActive() && $this->context->shop() == Shop::CONTEXT_SHOP)
+				$this->_category = new Category($this->context->shop->id_category);
+			else
+				$this->_category = Category::getTopCategory();
 	}
 	
 	public function initContent()
@@ -123,22 +126,22 @@ class AdminCategoriesControllerCore extends AdminController
 		$this->addRowAction('view');
 
 		$count_categories_without_parent = count(Category::getCategoriesWithoutParent());
-		$nb_shop = count(Shop::getShops());
+		$is_multishop = Shop::isFeatureActive();
 		if (Tools::isSubmit('id_category'))
 			$id_parent = $this->_category->id;
-		else if ($nb_shop == 1 && $count_categories_without_parent > 1)
-			$id_parent = 0;
-		else if ($nb_shop > 1 && $count_categories_without_parent == 1)
+		else if (!$is_multishop && $count_categories_without_parent > 1)
+			$id_parent = 1;
+		else if ($is_multishop && $count_categories_without_parent == 1)
+			$id_parent = 2;
+		else if ($is_multishop && $count_categories_without_parent > 1 && $this->context->shop() != Shop::CONTEXT_SHOP)
 			$id_parent = 1;
-		else if ($nb_shop > 1 && $count_categories_without_parent > 1 && $this->context->shop() != Shop::CONTEXT_SHOP)
-			$id_parent = 0;
 		else
 			$id_parent = $this->context->shop->id_category;
 
 		$this->_filter .= ' AND `id_parent` = '.(int)$id_parent.' ';
 		$this->_select = 'position ';
 		// we add restriction for shop
-		if (Shop::CONTEXT_SHOP == Context::getContext()->shop() && $nb_shop > 1)
+		if (Shop::CONTEXT_SHOP == Context::getContext()->shop() && $is_multishop)
 		{
 			$this->_join = 'LEFT JOIN `'._DB_PREFIX_.'category_shop` cs ON a.`id_category` = cs.`id_category`';
 			$this->_where = ' AND cs.`id_shop` = '.(int)Context::getContext()->shop->getID(true);
@@ -147,29 +150,11 @@ class AdminCategoriesControllerCore extends AdminController
 		$categories_tree = $this->_category->getParentsCategories();
 		if (empty($categories_tree)
 			&& ($this->_category->id_category != 1 || Tools::isSubmit('id_category'))
-			&& (Shop::CONTEXT_SHOP == Context::getContext()->shop() && $nb_shop == 1 && $count_categories_without_parent > 1))
+			&& (Shop::CONTEXT_SHOP == Context::getContext()->shop() && !$is_multishop && $count_categories_without_parent > 1))
 			$categories_tree = array(array('name' => $this->_category->name[$this->context->language->id]));
 
 		asort($categories_tree);
-		if ($nb_shop == 1 && $count_categories_without_parent > 1)
-			$categories_name = $this->l('Root');
-		else
-			if ($this->_category->getName() == '')
-			{
-				$categories_name = new Category($id_parent);
-				$categories_name = stripslashes($categories_name->getName());
-			}
-			else
-				$categories_name = stripslashes($this->_category->getName());
-		$root = Category::getRootCategory();
-		if (!is_array($root->name) && empty($root->name))
-		{
-			$root->name = $this->l('Root');
-			$root->id = $root->id_category = 0;
-		}
 		$this->tpl_list_vars['categories_tree'] = $categories_tree;
-		$this->tpl_list_vars['categories_name'] = $categories_name;
-		$this->tpl_list_vars['category_root'] = $root;
 
 		if (Tools::isSubmit('submitBulkdelete'.$this->table) OR Tools::isSubmit('delete'.$this->table))
 			$this->tpl_list_vars['delete_category'] = true;
@@ -271,10 +256,7 @@ class AdminCategoriesControllerCore extends AdminController
 		$guest_group_information = sprintf($this->l('%s - Customer who placed an order with the Guest Checkout.'), "<b>".$guest->name[$this->context->language->id]."</b>");
 		$default_group_information = sprintf($this->l('%s - All persons who created an account on this site.'), "<b>".$default->name[$this->context->language->id]."</b>");
 		$root_category = Category::getRootCategory();
-		if (!$root_category->id_category)
-			$root_category = array('id_category' => '0', 'name' => $this->l('Root'));
-		else
-			$root_category = array('id_category' => $root_category->id_category, 'name' => $root_category->name);
+		$root_category = array('id_category' => $root_category->id_category, 'name' => $root_category->name[$this->context->language->id]);
 		$this->fields_form = array(
 			'tinymce' => true,
 			'legend' => array(
@@ -451,10 +433,7 @@ class AdminCategoriesControllerCore extends AdminController
 		$id_parent = (int)Tools::getValue('id_parent');
 		// if true, we are in a root category creation
 		if (!$id_parent && !Tools::isSubmit('is_root_category'))
-		{
-			$_POST['id_parent'] = $id_parent = 0;
-			$_POST['is_root_category'] = 1;
-		}
+			$_POST['is_root_category'] = $_POST['level_depth'] = $_POST['id_parent'] = $id_parent = 1;
 		if ($id_category)
 		{
 			if ($id_category != $id_parent)
diff --git a/controllers/admin/AdminGroupsController.php b/controllers/admin/AdminGroupsController.php
index 7cfe1c997..edf06cc31 100644
--- a/controllers/admin/AdminGroupsController.php
+++ b/controllers/admin/AdminGroupsController.php
@@ -247,13 +247,8 @@ class AdminGroupsControllerCore extends AdminController
 				)
 			)
 		);
-		if ($this->context->shop() == Shop::CONTEXT_SHOP)
-		{
-			$root_category = Category::getRootCategory();
-			$root_category = array('id_category' => $root_category->id_category, 'name' => $root_category->name);
-		}
-		else
-			$root_category = array('id_category' => '0', 'name' => $this->l('Root'));
+		$root_category = Category::getRootCategory();
+		$root_category = array('id_category' => $root_category->id_category, 'name' => $root_category->name[$this->context->language->id]);
 		$this->fields_value['reduction'] = isset($group->reduction) ? $group->reduction : 0;
 
 		$trads = array(
diff --git a/controllers/admin/AdminProductsController.php b/controllers/admin/AdminProductsController.php
index 3d63d6f96..226310aae 100644
--- a/controllers/admin/AdminProductsController.php
+++ b/controllers/admin/AdminProductsController.php
@@ -2472,12 +2472,7 @@ class AdminProductsControllerCore extends AdminController
 				$selected_cat = Product::getProductCategoriesFull($product->id, $this->default_form_language);
 		}
 		$root_category = Category::getRootCategory();
-		if (!$root_category->id_category)
-		{
-			$root_category->id_category = 0;
-			$root_category->name = $this->l('Root');
-		}
-		$root_category = array('id_category' => $root_category->id_category, 'name' => $root_category->name);
+		$root_category = array('id_category' => $root_category->id_category, 'name' => $root_category->name[$this->context->language->id]);
 		$translations = array(
 			'Root' => $root_category,
 			'selected' => $this->l('selected'),
diff --git a/install-new/data/xml/category.xml b/install-new/data/xml/category.xml
index ae59944b2..45845ae0f 100644
--- a/install-new/data/xml/category.xml
+++ b/install-new/data/xml/category.xml
@@ -5,6 +5,7 @@
     <field name="active"/>
   </fields>
   <entities>
-    <category id="Home" id_parent="" active="1" is_root_category="1"/>
+    <category id="Root" id_parent="" active="1"/>
+    <category id="Home" id_parent="Root" active="1" is_root_category="1"/>
   </entities>
 </entity_category>
diff --git a/install-new/langs/de/data/category.xml b/install-new/langs/de/data/category.xml
index 21fbec134..6e692ef85 100644
--- a/install-new/langs/de/data/category.xml
+++ b/install-new/langs/de/data/category.xml
@@ -1,5 +1,13 @@
 <?xml version="1.0"?>
 <entity_category>
+  <category id="Root" id_shop="1">
+    <name>Root</name>
+    <description/>
+    <link_rewrite>root</link_rewrite>
+    <meta_title/>
+    <meta_keywords/>
+    <meta_description/>
+  </category>
   <category id="Home" id_shop="1">
     <name>Start</name>
     <description/>
diff --git a/install-new/langs/en/data/category.xml b/install-new/langs/en/data/category.xml
index 75b64387f..3c34ab702 100644
--- a/install-new/langs/en/data/category.xml
+++ b/install-new/langs/en/data/category.xml
@@ -1,5 +1,13 @@
 <?xml version="1.0"?>
 <entity_category>
+    <category id="Root" id_shop="1">
+      <name>Root</name>
+      <description/>
+      <link_rewrite>root</link_rewrite>
+      <meta_title/>
+      <meta_keywords/>
+      <meta_description/>
+    </category>
   <category id="Home" id_shop="1">
     <name>Home</name>
     <description/>
diff --git a/install-new/langs/es/data/category.xml b/install-new/langs/es/data/category.xml
index 5441ac0c1..929aa84de 100644
--- a/install-new/langs/es/data/category.xml
+++ b/install-new/langs/es/data/category.xml
@@ -1,5 +1,13 @@
 <?xml version="1.0"?>
 <entity_category>
+    <category id="Root" id_shop="1">
+      <name>Root</name>
+      <description/>
+      <link_rewrite>root</link_rewrite>
+      <meta_title/>
+      <meta_keywords/>
+      <meta_description/>
+    </category>
   <category id="Home" id_shop="1">
     <name>Inicio</name>
     <description/>
diff --git a/install-new/langs/fr/data/category.xml b/install-new/langs/fr/data/category.xml
index 969e6f73a..6389d16b9 100644
--- a/install-new/langs/fr/data/category.xml
+++ b/install-new/langs/fr/data/category.xml
@@ -1,5 +1,13 @@
 <?xml version="1.0"?>
 <entity_category>
+    <category id="Root" id_shop="1">
+      <name>Root</name>
+      <description/>
+      <link_rewrite>root</link_rewrite>
+      <meta_title/>
+      <meta_keywords/>
+      <meta_description/>
+    </category>
   <category id="Home" id_shop="1">
     <name>Accueil</name>
     <description/>
diff --git a/install-new/langs/it/data/category.xml b/install-new/langs/it/data/category.xml
index 8fcc95190..3477765f4 100644
--- a/install-new/langs/it/data/category.xml
+++ b/install-new/langs/it/data/category.xml
@@ -1,5 +1,13 @@
 <?xml version="1.0"?>
 <entity_category>
+    <category id="Root" id_shop="1">
+      <name>Root</name>
+      <description/>
+      <link_rewrite>root</link_rewrite>
+      <meta_title/>
+      <meta_keywords/>
+      <meta_description/>
+    </category>
   <category id="Home" id_shop="1">
     <name>Home page</name>
     <description/>
diff --git a/install-new/models/install.php b/install-new/models/install.php
index e2638bd21..3e71dce1e 100644
--- a/install-new/models/install.php
+++ b/install-new/models/install.php
@@ -219,7 +219,7 @@ class InstallModelInstall extends InstallAbstractModel
 		$shop = new Shop();
 		$shop->active = true;
 		$shop->id_group_shop = $group_shop->id;
-		$shop->id_category = 1;
+		$shop->id_category = 2;
 		$shop->id_theme = 1;
 		$shop->name = 'Default';
 		if (!$shop->add())
diff --git a/install-new/upgrade/php/generate_root_category_for_multishop.php b/install-new/upgrade/php/generate_root_category_for_multishop.php
new file mode 100644
index 000000000..649c94d36
--- /dev/null
+++ b/install-new/upgrade/php/generate_root_category_for_multishop.php
@@ -0,0 +1,44 @@
+<?php
+
+function generate_root_category_for_multishop()
+{
+	Db::getInstance()->execute('
+		UPDATE `'._DB_PREFIX_.'category` SET `level_depth`=`level_depth`+1
+	');
+
+	Db::getInstance()->execute('
+		INSERT INTO `'._DB_PREFIX_.'category` (`id_parent`, `level_depth`, `active`, `date_add`, `date_upd`, `is_root_category`) VALUES
+		(0, 0, 1, NOW(), NOW(), 0)
+	');
+	$id = Db::getInstance()->Insert_ID();
+
+	$langs = Db::getInstance()->executeS('
+		SELECT `id_lang`
+		FROM `'._DB_PREFIX_.'lang`
+	');
+
+	$shops = Db::getInstance()->executeS('
+		SELECT `id_shop`
+		FROM `'._DB_PREFIX_.'shop`
+	');
+
+	$data = array();
+	foreach ($langs as $lang)
+		foreach ($shops as $shop)
+			$data[] = array(
+				'id_lang' => $lang['id_lang'],
+				'id_shop' => $shop['id_shop'],
+				'id_category' => $id,
+				'name' => 'Root',
+				'link_rewrite' => '',
+			);
+	Db::getInstance()->autoExecute(_DB_PREFIX_.'category_lang', $data, 'INSERT');
+
+	Db::getInstance()->execute('
+		UPDATE `'._DB_PREFIX_.'category`
+		SET `id_parent` = '.(int)$id.'
+		WHERE `id_parent` = 0 AND `id_category` <> '.(int)$id.'
+	');
+
+	Category::regenerateEntireNtree();
+}
\ No newline at end of file
diff --git a/install-new/upgrade/sql/1.5.0.4.sql b/install-new/upgrade/sql/1.5.0.4.sql
index e6f161ef7..cc4df1543 100644
--- a/install-new/upgrade/sql/1.5.0.4.sql
+++ b/install-new/upgrade/sql/1.5.0.4.sql
@@ -18,3 +18,14 @@ WHERE `name` = "order fenced" AND (`id_lang` = 1 OR `id_lang` = 3 OR `id_lang` =
 UPDATE `PREFIX_supply_order_state_lang` 
 SET `name` = "Commande cloturée" 
 WHERE `name` = "order fenced" AND id_lang = 2;
+
+
+CREATE TABLE `PREFIX_category_shop` (
+  `id_category` int(11) NOT NULL,
+  `id_shop` int(11) NOT NULL,
+  PRIMARY KEY (`id_category`, `id_shop`),
+  UNIQUE KEY `id_category_shop` (`id_category`,`id_shop`)
+) ENGINE=ENGINE_TYPE  DEFAULT CHARSET=utf8;
+
+
+/* PHP:generate_root_category_for_multishop(); */;
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