diff --git a/materiels.tar.gz b/materiels.tar.gz
index 9b42823..11982c1 100644
Binary files a/materiels.tar.gz and b/materiels.tar.gz differ
diff --git a/src/lib/Entry.php b/src/lib/Entry.php
index c9e33ac..41a2270 100644
--- a/src/lib/Entry.php
+++ b/src/lib/Entry.php
@@ -3,6 +3,7 @@
 namespace Garradin\Plugin\Materiels;
 
 use Garradin\DB;
+use Garradin\Plugin\Materiels\Equipment;
 
 class Entry
 {
@@ -31,4 +32,24 @@ class Entry
 	{
 		return DB::getInstance()->get('SELECT * FROM plugin_materiels_entry ORDER BY entry_date DESC;');
 	}
+
+  public function PossibilityRentEqmtEntry($id, $eqmt_number, $date)
+	{
+    $after_entry_dates = DB::getInstance()->get(
+      "SELECT entry_date FROM plugin_materiels_entry WHERE kind = 'Retour de location / prêt' AND equipment_id = '{$id}' AND entry_date > '{$date}';");
+    $entry_dates = array($date);
+    foreach ($after_entry_dates as $row)
+    {
+      array_push($entry_dates, $row->entry_date);
+    }
+    $eqmt = new Equipment;
+    foreach ($entry_dates as $entry_date) {
+      $out_of_stock_eqmt = $eqmt->CalculateOutOfStockByDate($id, $entry_date);
+      if ($out_of_stock_eqmt - $eqmt_number < 0)
+      {
+        return false;
+      }
+    }
+    return true;
+	}
 }
diff --git a/src/lib/Equipment.php b/src/lib/Equipment.php
index b3b671d..fd23201 100644
--- a/src/lib/Equipment.php
+++ b/src/lib/Equipment.php
@@ -65,7 +65,7 @@ class Equipment
     return $entries - $outputs;
   }
 
-  public function GetAllListByCategory()
+  public function AllListsAllByCategory()
   {
     $eqmts_by_cat = $this->listAllByCategory();
     $eqmts_owned_by_cat = array();
@@ -119,7 +119,7 @@ class Equipment
     return $entries - $outputs;
   }
 
-  public function GetAvailableListByCategory()
+  public function ListAllAvailableByCategory()
   {
     $eqmts_by_cat = $this->listAllByCategory();
     $eqmts_available_by_cat = array();
@@ -151,4 +151,33 @@ class Equipment
         'Location / Prêt') AND equipment_id = '{$id}' AND output_date <= '{$date}';");
     return $entries - $outputs;
   }
+
+  public function listAllReleasedRentByCategory()
+  {
+    $eqmts_by_cat = $this->listAllByCategory();
+    $eqmts_borrowed_by_cat = array();
+    foreach ($eqmts_by_cat as $cat => $eqmts) {
+      $eqmts_borrowed = array();
+      foreach ($eqmts as $eqmt) {
+        $borrowed = $this->CalculateOutOfStock($eqmt->id);
+        if ($borrowed) {
+          $eqmt->borrowed = $borrowed;
+          array_push($eqmts_borrowed, $eqmt);
+        }
+      }
+      if ($eqmts_borrowed) {
+        $eqmts_borrowed_by_cat[$cat] = $eqmts_borrowed;
+      }
+    }
+    return $eqmts_borrowed_by_cat;
+  }
+
+  public function CalculateOutOfStockByDate($id, $date)
+  {
+    $entries = DB::getInstance()->firstColumn(
+      "SELECT sum(equipment_number) FROM plugin_materiels_entry WHERE kind = 'Retour de location / prêt' AND equipment_id = '{$id}' AND entry_date <= '{$date}';");
+    $outputs = DB::getInstance()->firstColumn(
+      "SELECT sum(equipment_number) FROM plugin_materiels_output WHERE kind = 'Location / Prêt' AND equipment_id = '{$id}' AND output_date <= '{$date}';");
+    return $outputs - $entries;
+  }
 }
diff --git a/src/templates/entrees/retour.tpl b/src/templates/entrees/retour.tpl
index 37795a6..1fc3c03 100644
--- a/src/templates/entrees/retour.tpl
+++ b/src/templates/entrees/retour.tpl
@@ -8,7 +8,7 @@
           {if $eqmts}
             <optgroup label="-- {$cat} --">
               {foreach from=$eqmts item="eqmt"}
-                <option value="{$eqmt.id}">{$eqmt.designation}</option>
+                <option value="{$eqmt.id}"{if ($selected_eqmt !== "") && ($selected_eqmt == $eqmt.id)} selected="selected"{/if}>{$eqmt.designation} - sortie: {$eqmt.borrowed}</option>
               {/foreach}
             </optgroup>
           {/if}
diff --git a/src/templates/index.tpl b/src/templates/index.tpl
index 55dbb3f..e90de43 100644
--- a/src/templates/index.tpl
+++ b/src/templates/index.tpl
@@ -33,7 +33,7 @@
 	{/if}
 {/foreach}
 
-<h2>Matériel dont l'association n'est pas propriétaire (loué ou prêté)</h2>
+<h2>Matériel dont l'association n'est pas propriétaire (emprunté)</h2>
 {foreach from=$eqmts_no_owned_by_cat key='cat' item="eqmts"}
 	{if $eqmts}
 		<h3>{$cat}</h3>
diff --git a/src/templates/sorties/stock_disponible.tpl b/src/templates/sorties/stock_disponible.tpl
index c13c432..37ff335 100644
--- a/src/templates/sorties/stock_disponible.tpl
+++ b/src/templates/sorties/stock_disponible.tpl
@@ -7,7 +7,7 @@
         {foreach from=$eqmts_by_cat key='cat' item="eqmts"}
           <optgroup label="-- {$cat} --">
             {foreach from=$eqmts item="eqmt"}
-              <option value="{$eqmt.id}"{if ($selected_eqmt !== "") && ($selected_eqmt == $eqmt.id)} selected="selected"{/if}>{$eqmt.designation} - (dispo: {$eqmt.available})</option>
+              <option value="{$eqmt.id}"{if ($selected_eqmt !== "") && ($selected_eqmt == $eqmt.id)} selected="selected"{/if}>{$eqmt.designation} - dispo: {$eqmt.available}</option>
             {/foreach}
           </optgroup>
         {/foreach}
diff --git a/src/www/admin/entrees/retour.php b/src/www/admin/entrees/retour.php
index f9f9711..39e95af 100644
--- a/src/www/admin/entrees/retour.php
+++ b/src/www/admin/entrees/retour.php
@@ -8,36 +8,51 @@ use Garradin\Utils;
 
 require_once __DIR__ . '/../_inc.php';
 
-$csrf_key = 'add_entry';
-
-if (f('save') && $form->check($csrf_key) && !$form->hasErrors())
-{
-  if ($form->check($csrf_key) && !$form->hasErrors())
-  {
-    $entry = new Entry;
-    $entry_date_format = date_create_from_format(
-      "d/m/Y", f('entry_date'))->format("Y-m-d");
-    $entry->add([
-      'kind' => 'Retour de location / prêt',
-      'equipment_number' => (int) f('equipment_number'),
-      'equipment_id' => f('equipment_id'),
-      'entry_date' => $entry_date_format,
-      'additional_comment' => f('additional_comment'),
-    ]);
-  	Utils::redirect(PLUGIN_URL . 'entrees/index.php');
-  }
-}
-
+$entry = new Entry;
 $eqmt = new Equipment;
-$eqmts_by_cat = $eqmt->listAllByCategory();
+
+$eqmts_by_cat = $eqmt->listAllReleasedRentByCategory();
+$selected_eqmt = "";
 
 $date = new \DateTime;
 $date->setTimestamp(time());
 $default_date = $date;
 
-$default_number = "1";
 $default_comment = "";
 
+$csrf_key = 'add_entry';
+
+if (f('save') && $form->check($csrf_key) && !$form->hasErrors())
+{
+  $eqmt_id = f('equipment_id');
+  $eqmt_number = (int) f('equipment_number');
+  $entry_date_format = date_create_from_format(
+    "d/m/Y", f('entry_date'))->format("Y-m-d");
+  if ($entry->PossibilityRentEqmtEntry($eqmt_id, $eqmt_number, $entry_date_format))
+  {
+    $entry->add([
+      'kind' => 'Retour de location / prêt',
+      'equipment_number' => $eqmt_number,
+      'equipment_id' => $eqmt_id,
+      'entry_date' => $entry_date_format,
+      'additional_comment' => f('additional_comment'),
+    ]);
+  	Utils::redirect(PLUGIN_URL . 'entrees/index.php');
+  } else
+  {
+    $entry_date = f('entry_date');
+    $selected_eqmt = $eqmt_id;
+    $default_date = $entry_date;
+    $default_comment = f('additional_comment');
+
+    $equiment = $eqmt->get($eqmt_id);
+    $form->addError(
+      "Il est impossible de rentrer " . (string) $eqmt_number . " " . $equiment->designation . " à la date du " . (string) $entry_date . '.');
+  }
+}
+
+$default_number = "1";
+
 $cancel_link = PLUGIN_URL . 'entrees/index.php';
 $legend_part = "en retour de location / prêt";
 $tpl_materiel_name = "retour";
@@ -45,7 +60,7 @@ $tpl_materiel_name = "retour";
 $tpl->assign(compact(
   'eqmts_by_cat', 'default_date', 'default_number',
   'default_comment', 'cancel_link', 'legend_part',
-  'tpl_materiel_name', 'csrf_key'
+  'tpl_materiel_name', 'csrf_key', 'selected_eqmt',
 ));
 
 $tpl->display(PLUGIN_ROOT . '/templates/entrees/ajouter_entree.tpl');
diff --git a/src/www/admin/index.php b/src/www/admin/index.php
index 39ae74e..3bc0237 100644
--- a/src/www/admin/index.php
+++ b/src/www/admin/index.php
@@ -15,7 +15,7 @@ $eqmt = new Equipment;
 
 list(
 	$eqmts_owned_by_cat, $eqmts_no_owned_by_cat,
-	$eqmts_just_listed_by_cat) = $eqmt->GetAllListByCategory();
+	$eqmts_just_listed_by_cat) = $eqmt->AllListsAllByCategory();
 
 $tpl->assign(compact(
 	'eqmts_owned_by_cat', 'eqmts_no_owned_by_cat',
diff --git a/src/www/admin/sorties/stock_disponible.php b/src/www/admin/sorties/stock_disponible.php
index 4e45c48..2b35c40 100644
--- a/src/www/admin/sorties/stock_disponible.php
+++ b/src/www/admin/sorties/stock_disponible.php
@@ -11,7 +11,7 @@ require_once __DIR__ . '/../_inc.php';
 $output = new Output;
 $eqmt = new Equipment;
 
-$eqmts_by_cat = $eqmt->GetAvailableListByCategory();
+$eqmts_by_cat = $eqmt->ListAllAvailableByCategory();
 $selected_eqmt = "";
 
 $kinds = $output->listKinds();
@@ -49,7 +49,7 @@ if (f('save') && $form->check($csrf_key) && !$form->hasErrors())
     $default_date = $output_date;
     $default_comment = f('additional_comment');
 
-    $equiment = $eqmt->get(f('equipment_id'));
+    $equiment = $eqmt->get($eqmt_id);
     $form->addError(
       "Il est impossible de sortir " . (string) $eqmt_number . " " . $equiment->designation . " à la date du " . (string) $output_date . '.');
   }