diff --git a/inc/GlobalPaybacks.class.php b/inc/GlobalPaybacks.class.php
new file mode 100644
index 0000000..00d05aa
--- /dev/null
+++ b/inc/GlobalPaybacks.class.php
@@ -0,0 +1,108 @@
+<?php
+    require_once('data/config.php');
+    require_once('Storage.class.php');
+    require_once('UsersInGlobalPayback.class.php');
+
+    class GlobalPayback extends Storage {
+        protected $id = 0, $date, $users_in;
+        // date is a DateTime object
+        // buyer is a User object
+        // users_in is a UsersIn objects
+        protected $TABLE_NAME = "GlobalPaybacks";
+        protected $fields = array(
+            'id'=>'key',
+            'date'=>'date',
+            );
+
+        public function __construct() {
+            parent::__construct();
+            $this->users_in = new UsersInGlobalPayback();
+        }
+
+        // Getters
+        // =======
+        public function getId() {
+            return $this->id;
+        }
+
+        public function getDate($format = "d-m-Y H:i") {
+            if(!empty($this->date))
+                return $this->date->format($format);
+            else
+                return false;
+        }
+
+        public function getUsersIn() {
+            return $this->users_in;
+        }
+
+        // Setters
+        // =======
+        public function setId($id) {
+            $this->users_in->setInvoiceId($id);
+            $this->id = (int) $id;
+        }
+
+        public function setDate($minute, $hour, $day, $month, $year) {
+            if((int) $minute < 10) $minute = '0'.$minute;
+
+            $this->date = DateTime::createFromFormat('Y-n-j G:i', $year.'-'.(int) $month.'-'.(int) $day.' '.(int) $hour.':'.$minute);
+        }
+
+        public function setUsersIn($users_in) {
+            // Note : users_in in param is an array with users in listed and guests for each user
+            $this->users_in->set($users_in);
+        }
+
+        // Maps htmlspecialchars on the class before display
+        // =================================================
+        public function secureDisplay() {
+            $this->id = (int) $this->id;
+
+            return $this;
+        }
+
+        // Restores object from array
+        // ==========================
+        public function sessionRestore($data, $serialized = false) {
+            if($serialized) {
+                $data = unserialize($data);
+            }
+
+            $this->setId($data['id']);
+            $this->date = DateTime::createFromFormat('Y-m-d H:i:s', $data['date']);
+        }
+        
+        // Override parent load() method
+        // =============================
+        public function load($fields = NULL, $first_only = false) {
+            $return = parent::load($fields, $first_only); // Execute parent load
+
+            if(is_array($return)) {
+                foreach(array_keys($return) as $key) {
+                    $return[$key]->users_in->load(); // Load users in for each global paybacks
+                }
+            }
+            elseif(is_a($return, 'GlobalPayback')) {
+                $return->users_in->load();
+            }
+
+            return $return; // Return the loaded elements
+        }
+
+        // Override parent save() method
+        // ============================
+        public function save() {
+            parent::save(); // Save invoice element
+
+            $this->users_in->save(); // Save users in
+        }
+
+        // Override parent delete() method
+        // ===============================
+        public function delete() {
+            parent::delete(); // Delete invoice element
+
+            $this->users_in->delete(); // Also delete users in
+        }
+    }
diff --git a/inc/UsersIn.class.php b/inc/UsersIn.class.php
index e449f46..f740b1f 100644
--- a/inc/UsersIn.class.php
+++ b/inc/UsersIn.class.php
@@ -58,7 +58,7 @@
             foreach($this->users_list as $user=>$guests) {
                 $temp_array[(int) $user] = (int) $guests;
             }
-            $this->users_in = $temp_array;
+            $this->users_list = $temp_array;
 
             return $this;
         }
diff --git a/inc/UsersInGlobalPayback.class.php b/inc/UsersInGlobalPayback.class.php
new file mode 100644
index 0000000..9c35374
--- /dev/null
+++ b/inc/UsersInGlobalPayback.class.php
@@ -0,0 +1,132 @@
+<?php
+    require_once('data/config.php');
+    require_once('Storage.class.php');
+
+    class UsersInGlobalPayback extends Storage {
+        protected $payback_id = 0, $users_list;
+        //users_list is a 2D array of users_id and amount between them
+        //user1 owes amount to user2
+        protected $TABLE_NAME = "Users_in_GlobalPayback";
+        protected $fields = array(
+            'global_payback_id'=>'int',
+            'user1_id'=>'int',
+            'user2_id'=>'int',
+            'amount'=>'float'
+            );
+
+        public function __construct() {
+            parent::__construct();
+            $users_list = array();
+        }
+
+        // Getters
+        // =======
+        public function getPaybackId() {
+            return $this->payback_id;
+        }
+
+        public function get() {
+            return $this->users_list;
+        }
+
+        // Setters
+        // =======
+        public function setPaybackId($id) {
+            $this->payback_id = (int) $id;
+        }
+
+        public function set($users_in) {
+            $this->users_list = $users_in;
+        }
+
+        // Maps htmlspecialchars on the class before display
+        // =================================================
+        public function secureDisplay() {
+            $this->payback_id = (int) $this->payback_id;
+
+            $temp_array = array();
+            foreach($this->users_list as $user1=>$temp) {
+                foreach($temp as $user2=>$amount) {
+                    $temp_array[(int) $user1][(int) [$user2]] = (float) $amount;
+                }
+            }
+            $this->users_list = $temp_array;
+
+            return $this;
+        }
+
+        // Override load() method
+        // ======================
+        public function load() {
+            $query = 'SELECT ';
+
+            $i = false;
+            foreach($this->fields as $field=>$type) {
+                if($i) { $query .= ','; } else { $i = true; }
+
+                $query .= $field;
+            }
+
+            $query .= ' FROM '.MYSQL_PREFIX.$this->TABLE_NAME.' WHERE payback_id=:payback_id';
+
+            $query = $this->getConnection()->prepare($query);
+            $query->bindParam(':payback_id', $this->payback_id);
+            $query->execute();
+
+            $results = $query->fetchAll();
+            $this->users_list = array();
+            foreach($results as $result) {
+                $this->users_list[(int) $result['user1_id']][(int) $result['user2_id']] = (float) $result['amount'];
+            }
+        }
+
+        // Override save() method
+        // ======================
+        public function save() {
+            // TODO : Optimize ?
+
+            $query = 'SELECT COUNT(payback_id) FROM '.MYSQL_PREFIX.$this->TABLE_NAME.' WHERE payback_id=:payback_id';
+            $query = $this->getConnection()->prepare($query);
+            $query->bindParam(':payback_id', $this->payback_id);
+            $query->execute();
+
+            $count = $query->fetchColumn(0);
+
+            if($count != 0) {
+                // If there are already some records, delete them first
+                $query = $this->getConnection()->prepare('DELETE FROM '.MYSQL_PREFIX.$this->TABLE_NAME.' WHERE payback_id=:payback_id');
+                $query->bindParam(':payback_id', $this->payback_id);
+                $query->execute();
+            }
+
+            $query = 'INSERT INTO '.MYSQL_PREFIX.$this->TABLE_NAME.'(';
+            $i = false;
+            foreach($this->fields as $field=>$type) {
+                if($i) { $query .= ','; } else { $i = true;}
+                $query .= $field;
+            }
+
+            $query .= ') VALUES(:payback_id, :user1_id, :user2_id, :amount)';
+
+            $query = $this->getConnection()->prepare($query);
+
+            $query->bindParam(':payback_id', $this->payback_id);
+
+            foreach($this->users_list as $user1=>$temp) {
+                foreach($temp as $user2=>$amount) {
+                    $query->bindParam(':user1_id', intval($user1));
+                    $query->bindParam(':user2_id', intval($user2));
+                    $query->bindParam(':amount', floatval($amount));
+                    $query->execute();
+                }
+            }
+        }
+
+        // Override delete() method
+        // ========================
+        public function delete() {
+            $query = $this->getConnection()->prepare('DELETE FROM '.MYSQL_PREFIX.$this->TABLE_NAME.' WHERE payback_id=:payback_id');
+            $query->bindParam(':payback_id', $this->payback_id);
+            $query->execute();
+        }
+    }
diff --git a/index.php b/index.php
index 8e406b4..23e6ff1 100644
--- a/index.php
+++ b/index.php
@@ -23,6 +23,7 @@
     require_once('inc/User.class.php');
     require_once('inc/Invoices.class.php');
     require_once('inc/Paybacks.class.php');
+    require_once('inc/GlobalPaybacks.class.php');
     require_once('inc/rain.tpl.class.php');
     require_once('inc/functions.php');
     require_once('inc/Ban.inc.php');
@@ -353,29 +354,29 @@
 
                             foreach($config as $line_number=>$line) {
                                 if(strpos(trim($line), "MYSQL_HOST") !== false)
-                                    $config[$line_number] = "\tdefine('MYSQL_HOST', '".$_POST['mysql_host']."');\n";
+                                    $config[$line_number] = "\tdefine('MYSQL_HOST', '".$_POST['mysql_host']."');";
                                 elseif(strpos(trim($line), "MYSQL_LOGIN") !== false)
-                                    $config[$line_number] = "\tdefine('MYSQL_LOGIN', '".$_POST['mysql_login']."');\n";
+                                    $config[$line_number] = "\tdefine('MYSQL_LOGIN', '".$_POST['mysql_login']."');";
                                 elseif(strpos(trim($line), "MYSQL_PASSWORD") !== false && !empty($_POST['mysql_password']))
-                                    $config[$line_number] = "\tdefine('MYSQL_PASSWORD', '".$_POST['mysql_password']."');\n";
+                                    $config[$line_number] = "\tdefine('MYSQL_PASSWORD', '".$_POST['mysql_password']."');";
                                 elseif(strpos(trim($line), "MYSQL_DB") !== false)
-                                    $config[$line_number] = "\tdefine('MYSQL_DB', '".$_POST['mysql_db']."');\n";
+                                    $config[$line_number] = "\tdefine('MYSQL_DB', '".$_POST['mysql_db']."');";
                                 elseif(strpos(trim($line), "MYSQL_PREFIX") !== false && !empty($_POST['mysql_prefix']))
-                                    $config[$line_number] = "\tdefine('MYSQL_PREFIX', '".$_POST['mysql_prefix']."');\n";
+                                    $config[$line_number] = "\tdefine('MYSQL_PREFIX', '".$_POST['mysql_prefix']."');";
                                 elseif(strpos(trim($line), "INSTANCE_TITLE") !== false)
-                                    $config[$line_number] = "\tdefine('INSTANCE_TITLE', '".$_POST['instance_title']."');\n";
+                                    $config[$line_number] = "\tdefine('INSTANCE_TITLE', '".$_POST['instance_title']."');";
                                 elseif(strpos(trim($line), "BASE_URL") !== false)
-                                    $config[$line_number] = "\tdefine('BASE_URL', '".$_POST['base_url']."');\n";
+                                    $config[$line_number] = "\tdefine('BASE_URL', '".$_POST['base_url']."');";
                                 elseif(strpos(trim($line), "CURRENCY") !== false)
-                                    $config[$line_number] = "\tdefine('CURRENCY', '".$_POST['currency']."');\n";
+                                    $config[$line_number] = "\tdefine('CURRENCY', '".$_POST['currency']."');";
                                 elseif(strpos(trim($line), "EMAIL_WEBMASTER") !== false)
-                                    $config[$line_number] = "\tdefine('EMAIL_WEBMASTER', '".$_POST['email_webmaster']."');\n";
+                                    $config[$line_number] = "\tdefine('EMAIL_WEBMASTER', '".$_POST['email_webmaster']."');";
                                 elseif(strpos(trim($line), "TEMPLATE_DIR") !== false)
-                                    $config[$line_number] = "\tdefine('TEMPLATE_DIR', 'tpl/".$_POST['template']."/');\n";
+                                    $config[$line_number] = "\tdefine('TEMPLATE_DIR', 'tpl/".$_POST['template']."/');";
                                 elseif(strpos(trim($line), "LANG") !== false)
-                                    $config[$line_number] = "\tdefine('LANG', '".substr($_POST['template'], -2)."');\n";
+                                    $config[$line_number] = "\tdefine('LANG', '".substr($_POST['template'], -2)."');";
                                 elseif(strpos(trim($line), 'date_default_timezone_set') !== false)
-                                    $config[$line_number] = "\tdate_default_timezone_set('".$_POST['timezone']."');\n";
+                                    $config[$line_number] = "\tdate_default_timezone_set('".$_POST['timezone']."');";
                             }
 
                             if(file_put_contents("data/config.php", $config)) {
@@ -675,6 +676,113 @@
             }
             break;
 
+        case "manage_paybacks":
+            if(empty($_GET['new'])) {
+                $tpl->assign('list', true);
+                $tpl->assign('global_paybacks', array(array("id"=>1, "date"=>"now")));
+            }
+            else {
+                if(!empty($_POST['users_in'])) {
+                    $global_payback = new GlobalPayback();
+
+                    // Backup database
+                    if(!is_dir('db_backup')) {
+                        mkdir('db_backup');
+                    }
+                    system("mysqldump -h ".MYSQL_HOST." -u ".MYSQL_LOGIN." -p ".MYSQL_PASSWORD." ".MYSQL_DB." > db_backup/".date('d-m-Y_H:i'));
+
+                    $users_in = array();
+                    foreach($_POST['users_in'] as $user1_id) {
+                        $user1_id = intval($user1_id);
+                        foreach($_POST['users_in'] as $user2_id) {
+                            $user2_id = intval($user2_id);
+                            if($user1_id == $user2_id) {
+                                $users_in[$user1_id][$user2_id] = 0;
+                            }
+                            elseif(!empty($users_in[$user2_id][$user1_id])) {
+                                if($users_in[$user2_id][$user1_id] > 0) {
+                                    $users_in[$user1_id][$user2_id] = 0;
+                                }
+                                else {
+                                    $users_in[$user1_id][$user2_id] = -$users_in[$user1_id][$user2_id];
+                                    $users_in[$user2_id][$user1_id] = 0;
+                                }
+                            }
+                            else {
+                                // Get the amount user1 owes to user2
+                                $users_in[$user1_id][$user2_id] = 0;
+
+                                // Confirm all paybacks when user2 is buyer
+                                $invoices = new Invoice();
+                                $invoices = $invoices->load(array('buyer'=>$user2_id));
+
+                                if($invoices !== false) {
+                                    foreach($invoices as $invoice) {
+                                        $paybacks = new Payback();
+                                        $paybacks = $paybacks->load(array('invoice_id'=>$invoice->getId(), 'to_user'=>$user2_id, 'from_user'=>$user1_id));
+
+                                        if($paybacks === false) {
+                                            $payback = new Payback();
+                                            $payback->setTo($user2_id);
+                                            $payback->setFrom($user1_id);
+                                            $payback->setAmount($invoice->getAmountPerPerson($user1_id));
+                                            $payback->setInvoice($invoice->getId());
+                                            $payback->setDate(date('i'), date('G'), date('j'), date('n'), date('Y'));
+                                            $payback->save();
+
+                                            // Add the amount to what user1 owes to user2
+                                            $users_in[$user1_id][$user2_id] += $payback->getAmount();
+                                        }
+                                    }
+                                }
+
+                                // Confirm all paybacks when from is buyer
+                                $invoices = new Invoice();
+                                $invoices = $invoices->load(array('buyer'=>$user1_id));
+
+                                if($invoices !== false) {
+                                    foreach($invoices as $invoice) {
+                                        $paybacks = new Payback();
+                                        $paybacks = $paybacks->load(array('invoice_id'=>$invoice->getId(), 'to_user'=>$user1_id, 'from_user'=>$user2_id));
+
+                                        if($paybacks === false) {
+                                            $payback = new Payback();
+                                            $payback->setTo($user1_id);
+                                            $payback->setFrom($user2_id);
+                                            $payback->setAmount($invoice->getAmountPerPerson($user2_id));
+                                            $payback->setInvoice($invoice->getId());
+                                            $payback->setDate(date('i'), date('G'), date('j'), date('n'), date('Y'));
+                                            $payback->save();
+
+                                            // Substract the amount to what user1 owes to user2
+                                            $users_in[$user1_id][$user2_id] -= $payback->getAmount();
+                                        }
+                                    }
+                                }
+                            }
+                        }
+                    }
+
+                    $global_payback->setUsersIn($users_in);
+                    $global_payback->setDate(date('i'), date('G'), date('j'), date('n'), date('Y'));
+                    $global_payback->save();
+
+                    // Clear the cache
+                    ($cached_files = glob(raintpl::$cache_dir."*.rtpl.php")) or ($cached_files = array());
+                    array_map("unlink", $cached_files);
+
+                    header('location: index.php?do=edit_users&'.$get_redir);
+                    exit();
+                }
+                
+                $users_list = new User();
+                $users_list = $users_list->load();
+
+                $tpl->assign('users', $users_list);
+            }
+            $tpl->draw('manage_paybacks');
+            break;
+
 
         default:
             if(empty($_GET['all']))
diff --git a/tpl/default_en/css/style.css b/tpl/default_en/css/style.css
index 06ebd14..1b4c4b8 100644
--- a/tpl/default_en/css/style.css
+++ b/tpl/default_en/css/style.css
@@ -63,6 +63,10 @@ input[type="checkbox"] {
     text-align: center;
 }
 
+.red {
+    color: red;
+}
+
 .label-block {
     display: inline-block;
     text-align: right;
diff --git a/tpl/default_fr/css/style.css b/tpl/default_fr/css/style.css
index 06ebd14..45d6680 100644
--- a/tpl/default_fr/css/style.css
+++ b/tpl/default_fr/css/style.css
@@ -10,6 +10,11 @@ body {
     margin: 0;
 }
 
+body>p, body>ul, body>dl {
+    margin-left: 1em;
+    margin-right: 1em;
+}
+
 fieldset {
     border: 1px solid #999;
     margin-bottom: 1em;
@@ -55,10 +60,20 @@ h2 {
     border-left: none;
 }
 
+hr {
+    width: 33%;
+    margin-top: 2em;
+    margin-bottom: 2em;
+}
+
 input[type="checkbox"] {
     margin-left: 2em;
 }
 
+.red {
+    color: red;
+}
+
 .center {
     text-align: center;
 }
@@ -120,12 +135,16 @@ input[type=submit] {
     text-align: center
 }
 
-#edit_password_form, #edit_user_form, #invoice_form, #notice_form {
+#edit_password_form, #edit_user_form, #invoice_form, #notice_form, #global_payback_form {
     width: 67%;
     margin: auto;
 }
 
-#edit_password_form p, #edit_user_form p, #notice_form p {
+#global_payback_form fieldset {
+    margin-top: 2em;
+}
+
+#edit_password_form p, #edit_user_form p, #notice_form p, #global_payback_form p {
     text-align: center;
 }
 
diff --git a/tpl/default_fr/manage_paybacks.html b/tpl/default_fr/manage_paybacks.html
new file mode 100644
index 0000000..c8ca15e
--- /dev/null
+++ b/tpl/default_fr/manage_paybacks.html
@@ -0,0 +1,43 @@
+{include="header"}
+
+{if condition="!empty($list)"}
+    <h2>Gérer les remboursements globaux</h2>
+        <p class="center"><a href="?do=manage_paybacks&new=1">Ajouter un remboursement global</a></p>
+
+        {if condition="count($global_paybacks) > 0"}
+            <p>Liste des remboursements globaux précédents :</p>
+            <dl>
+                {loop="$global_paybacks"}
+                    <dt>{$value['date']}</dt>
+                    <dd><a href="?do=see_paybacks&id={$value['id']}">Remboursement n°{$value['id']}</a></dd>
+                {/loop}
+            </dl>
+        {/if}
+{else}
+    <h2>Ajouter un remboursement global</h2>
+    <p>Cette page vous permet d'ajouter un remboursement global. Un tel remboursement permet de simplifier au maximum les remboursements. Ainsi, le tableau de la page d'accueil sera remis à zéro et un nouveau tableau sera créé, tableau qui simplifiera les échanges.</p>
+
+    <p>Par exemple, si A doit 5{$currency} à B et B doit 5{$currency} à C, après remboursement global, ces remboursements se simplifieront en A doit 5{$currency} à C.</p>
+
+    <p><strong>Note : <span class="red">Cette opération est irréversible sans mettre les mains dans la base de données.</span></strong></p>
+
+    <p><strong>Note :</strong> Un backup de votre base de données à l'heure actuelle sera effectué et stocké dans le répertoire backups à la racine de l'instance. Vous pourrez ainsi restaurer la base de données en cas d'erreur de votre part.</p>
+
+    <hr/>
+
+    <p>Si vous confirmez la création d'un remboursement global, veuillez sélectionner ci-dessous les utilisateurs que vous souhaitez inclure dans le remboursement.</p>
+
+    <form method="post" action="?do=manage_paybacks&new=1" id="global_payback_form">
+        <fieldset>
+            <legend>Utilisateurs à inclure</legend>
+            {loop="$users"}
+                <input type="checkbox" id="users_in_{$value->getId()}" name="users_in[]" value="{$value->getId()}"/>
+                <label for="users_in_{$value->getId()}">{$value->getDisplayName()}</label><br/>
+            {/loop}
+    </fieldset>
+    <p>
+        <input type="submit" onclick="confirm('Vous êtes sur le point d\'ajouter un remboursement global incluant les utilisateurs sélectionnés.');" value="Valider"/>
+    </p>
+    </form>
+{/if}
+{include="footer"}