diff --git a/addons/hr_payroll/__openerp__.py b/addons/hr_payroll/__openerp__.py
index 87fe437a1db..822573db480 100644
--- a/addons/hr_payroll/__openerp__.py
+++ b/addons/hr_payroll/__openerp__.py
@@ -57,6 +57,7 @@ Generic Payroll system.
         'security/ir.model.access.csv',
         'wizard/hr_payroll_employees_detail.xml',
         'wizard/hr_payroll_year_salary.xml',
+        'wizard/hr_payroll_payslips_by_category.xml',
     ],
     'test': [
 #         'test/payslip.yml',
diff --git a/addons/hr_payroll/hr_payroll.py b/addons/hr_payroll/hr_payroll.py
index 6757b57c417..55ec3d7995a 100644
--- a/addons/hr_payroll/hr_payroll.py
+++ b/addons/hr_payroll/hr_payroll.py
@@ -204,6 +204,15 @@ class one2many_mod2(fields.one2many):
             res[r[self._fields_id]].append( r['id'] )
         return res
 
+class hr_payslip_groups(osv.osv):
+
+    _name = 'hr.payslip.groups'
+    _columns = {
+        'name':fields.char('Name', size=256, required=True),
+        'slip_ids':fields.one2many('hr.payslip', 'payslip_group_id', 'Payslips', required=False, readonly=True),
+    }
+hr_payslip_groups()
+
 class hr_payslip(osv.osv):
     '''
     Pay Slip
@@ -215,13 +224,14 @@ class hr_payslip(osv.osv):
     def _get_lines_salary_head(self, cr, uid, ids, field_names, arg=None, context=None):
         result = {}
         if not ids: return result
+        for id in ids:
+            result.setdefault(id, [])
         cr.execute('''SELECT pl.slip_id, pl.id FROM hr_payslip_line AS pl \
                     LEFT JOIN hr_salary_head AS sh on (pl.category_id = sh.id) \
                     WHERE pl.slip_id in %s \
                     GROUP BY pl.slip_id, sh.sequence, pl.sequence, pl.id ORDER BY sh.sequence, pl.sequence''',(tuple(ids),))
         res = cr.fetchall()
         for r in res:
-            result.setdefault(r[0], [])
             result[r[0]].append(r[1])
         return result
 
@@ -255,6 +265,7 @@ class hr_payslip(osv.osv):
         'contract_id': fields.many2one('hr.contract', 'Contract', required=False, readonly=True, states={'draft': [('readonly', False)]}),
         'details_by_salary_head': fields.function(_get_lines_salary_head, method=True, type='one2many', relation='hr.payslip.line', string='Details by Salary Head'),
         'credit_note': fields.boolean('Credit Note', help="Indicates this payslip has a refund of another"),
+        'payslip_group_id': fields.many2one('hr.payslip.groups', 'Group', readonly=True, states={'draft': [('readonly', False)]}),
     }
     _defaults = {
         'date_from': lambda *a: time.strftime('%Y-%m-01'),
diff --git a/addons/hr_payroll/hr_payroll_view.xml b/addons/hr_payroll/hr_payroll_view.xml
index e1efc9d7f0c..e319b209011 100644
--- a/addons/hr_payroll/hr_payroll_view.xml
+++ b/addons/hr_payroll/hr_payroll_view.xml
@@ -188,8 +188,8 @@
             <field name="arch" type="xml">
                 <search string="Search Payslip Lines">
                     <group col="8" colspan="4">
-                    	<field name="name"/>
-                    	<field name="code"/>
+                        <field name="name"/>
+                        <field name="code"/>
                         <field name="slip_id"/>
                         <field name="amount_select"/>
                     </group>
@@ -211,7 +211,7 @@
             <field name="model">hr.payslip</field>
             <field name="type">tree</field>
             <field name="arch" type="xml">
-                <tree colors="blue:state in ('confirm','hr_check','accont_check');black:state in ('new');gray:state in('cancel')" string="Payslip">
+                <tree colors="blue:state in ('confirm','hr_check','accont_check');black:state in ('new');gray:state in('cancel')" string="Payslips">
                     <field name="number"/>
                     <field name="employee_id"/>
                     <field name="name"/>
@@ -278,7 +278,7 @@
                             </field>
                         </page>
 <!-- TODO: put me back -->
-	                    <page string="Details By Salary Head">
+                       <page string="Details By Salary Head">
                             <field name="details_by_salary_head" context="{'group_by':'category_id'}" domain="[('appears_on_payslip', '=', True)]" nolabel="1">
                                 <tree string="Payslip Lines">
                                     <field name="category_id"/>
@@ -549,14 +549,14 @@
                                 <field name="amount_select"/><newline/>
                                 <field name="amount_fix"  attrs="{'invisible':[('amount_select','&lt;&gt;','fix')], 'required':[('amount_select','=','fix')]}"/>
                                 <field colspan="4" name="amount_python_compute" attrs="{'invisible':[('amount_select','&lt;&gt;','code')], 'required':[('amount_select','=','code')]}"/>
-				<field name="amount_percentage_base" attrs="{'invisible':[('amount_select','&lt;&gt;','percentage')], 'required': [('amount_select','=','percentage')]}"/>
+                                <field name="amount_percentage_base" attrs="{'invisible':[('amount_select','&lt;&gt;','percentage')], 'required': [('amount_select','=','percentage')]}"/>
                                 <field name="amount_percentage" attrs="{'invisible':[('amount_select','&lt;&gt;','percentage')], 'required':[('amount_select','=','percentage')]}"/>
                                 <separator colspan="4" string="Company contribution"/>
                                 <field name="register_id"/>
                             </group>
                     </page>
                     <page string="Child Rules">
-		       <field name="parent_rule_id"/>
+                       <field name="parent_rule_id"/>
                        <separator colspan="4" string="Children definition"/>
                        <field colspan="4" name="child_ids" nolabel="1"/>
                     </page>
@@ -601,6 +601,38 @@
 
     <act_window domain="[('slip_id', '=', active_id)]" id="act_payslip_lines" name="Payslip Lines" res_model="hr.payslip.line" src_model="hr.payslip"/>
 
+    <record id="hr_payslip_category_tree" model="ir.ui.view">
+        <field name="name">hr.payslip.category.tree</field>
+        <field name="model">hr.payslip.groups</field>
+        <field name="type">tree</field>
+        <field name="arch" type="xml">
+            <tree string="Payslip Groups">
+                <field name="name"/>
+            </tree>
+        </field>
+    </record>
+
+    <record id="hr_payslip_category_form" model="ir.ui.view">
+        <field name="name">hr.payslip.category.form</field>
+        <field name="model">hr.payslip.groups</field>
+        <field name="type">form</field>
+        <field name="arch" type="xml">
+            <form string="Payslip by Category">
+                <group colspan="4">
+                    <field name="name"/>
+                </group>
+                <field name="slip_ids" colspan="4" nolabel="1"/>
+            </form>
+        </field>
+    </record>
+
+    <record id="action_hr_payslip_category_tree" model="ir.actions.act_window">
+        <field name="name">Payslips by Category</field>
+        <field name="res_model">hr.payslip.groups</field>
+        <field name="view_type">form</field>
+        <field name="view_id" ref="hr_payslip_category_tree"/>
+    </record>
+    <menuitem action="action_hr_payslip_category_tree" id="menu_hr_payslip_category" parent="menu_hr_root_payroll"/>
     </data>
 </openerp>
 
diff --git a/addons/hr_payroll/wizard/__init__.py b/addons/hr_payroll/wizard/__init__.py
index 2cf78e17b1c..fc8083099a5 100644
--- a/addons/hr_payroll/wizard/__init__.py
+++ b/addons/hr_payroll/wizard/__init__.py
@@ -1,7 +1,7 @@
 #-*- coding:utf-8 -*-
 ##############################################################################
 #
-#    OpenERP, Open Source Management Solution    
+#    OpenERP, Open Source Management Solution
 #    Copyright (C) 2004-2009 Tiny SPRL (<http://tiny.be>). All Rights Reserved
 #    d$
 #
@@ -24,5 +24,5 @@
 import hr_payroll_employees_detail
 #import hr_payroll_create_analytic
 import hr_payroll_year_salary
-
+import hr_payroll_payslips_by_category
 # vim:expandtab:smartindent:tabstop=4:softtabstop=4:shiftwidth=4:
\ No newline at end of file
diff --git a/addons/hr_payroll/wizard/hr_payroll_payslips_by_category.py b/addons/hr_payroll/wizard/hr_payroll_payslips_by_category.py
new file mode 100644
index 00000000000..9f8d9c010f9
--- /dev/null
+++ b/addons/hr_payroll/wizard/hr_payroll_payslips_by_category.py
@@ -0,0 +1,58 @@
+# -*- coding: utf-8 -*-
+##############################################################################
+#
+#    OpenERP, Open Source Management Solution
+#    Copyright (C) 2004-2010 Tiny SPRL (<http://tiny.be>).
+#
+#    This program is free software: you can redistribute it and/or modify
+#    it under the terms of the GNU Affero General Public License as
+#    published by the Free Software Foundation, either version 3 of the
+#    License, or (at your option) any later version.
+#
+#    This program is distributed in the hope that it will be useful,
+#    but WITHOUT ANY WARRANTY; without even the implied warranty of
+#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+#    GNU Affero General Public License for more details.
+#
+#    You should have received a copy of the GNU Affero General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+##############################################################################
+
+from osv import fields, osv
+import netsvc
+
+class hr_payroll_payslip_groups(osv.osv_memory):
+
+    _name ='hr.payroll.payslip.groups'
+    _columns = {
+            'employee_category': fields.many2one('hr.employee.category', 'Employee Category', required=True),
+    }
+
+    def compute_sheet(self, cr, uid, ids, context=None):
+        emp_pool = self.pool.get('hr.employee')
+        slip_pool = self.pool.get('hr.payslip')
+        wf_service = netsvc.LocalService("workflow")
+        if context is None:
+            context = {}
+        data = self.read(cr, uid, ids, context=context)[0]
+        cr.execute('SELECT DISTINCT emp_id FROM employee_category_rel WHERE category_id = %s', (data['employee_category'][0], ))
+        emp_ids = filter(None, map(lambda x:x[0], cr.fetchall()))
+        for emp in emp_pool.browse(cr, uid, emp_ids, context=context):
+            old_slips = slip_pool.search(cr, uid, [('employee_id','=', emp.id)], context=context)
+            if old_slips:
+                slip_pool.write(cr, uid, old_slips, {'payslip_group_id': context.get('active_id', False)}, context=context)
+                for sid in old_slips:
+                    wf_service.trg_validate(uid, 'hr.payslip', sid, 'compute_sheet', cr)
+            else:
+                res = {
+                    'employee_id': emp.id,
+                    'payslip_group_id': context.get('active_id', False),
+                }
+                slip_id = slip_pool.create(cr, uid, res, context=context)
+                wf_service.trg_validate(uid, 'hr.payslip', slip_id, 'compute_sheet', cr)
+        return {'type': 'ir.actions.act_window_close'}
+
+hr_payroll_payslip_groups()
+
+# vim:expandtab:smartindent:tabstop=4:softtabstop=4:shiftwidth=4:
diff --git a/addons/hr_payroll/wizard/hr_payroll_payslips_by_category.xml b/addons/hr_payroll/wizard/hr_payroll_payslips_by_category.xml
new file mode 100644
index 00000000000..394a894c024
--- /dev/null
+++ b/addons/hr_payroll/wizard/hr_payroll_payslips_by_category.xml
@@ -0,0 +1,45 @@
+<?xml version="1.0" encoding="utf-8"?>
+<openerp>
+    <data>
+
+        <record id="view_hr_payslip_by_category" model="ir.ui.view">
+            <field name="name">hr_payroll_payslip_category</field>
+            <field name="model">hr.payroll.payslip.groups</field>
+            <field name="type">form</field>
+            <field name="arch" type="xml">
+                <form string="Employee Category">
+                    <group colspan="4" >
+                        <separator string="Select Employee Category" colspan="4"/>
+                        <field name="employee_category"/>
+                    </group>
+                    <separator string="" colspan="4" />
+                    <group colspan="4" col="6">
+                        <label string ="" colspan="2"/>
+                        <button icon="gtk-cancel" special="cancel" string="Cancel"/>
+                        <button  icon="terp-gtk-go-back-rtl" string="Generate Payslip" name="compute_sheet" type="object"/>
+                    </group>
+               </form>
+            </field>
+        </record>
+
+        <record id="action_hr_payslip_by_category" model="ir.actions.act_window">
+            <field name="name">Generate Payslips by Category</field>
+            <field name="res_model">hr.payroll.payslip.groups</field>
+            <field name="view_type">form</field>
+            <field name="view_mode">tree,form</field>
+            <field name="view_id" ref="view_hr_payslip_by_category"/>
+            <field name="target">new</field>
+        </record>
+
+        <record id="action_idea_post_vote_values" model="ir.values">
+            <field name="model_id" ref="model_hr_payslip_groups" />
+            <field name="object" eval="1" />
+            <field name="name">Generate Payslips by Category</field>
+            <field name="key2">client_action_multi</field>
+            <field name="value" eval="'ir.actions.act_window,' + str(ref('action_hr_payslip_by_category'))"/>
+            <field name="key">action</field>
+            <field name="model">hr.payslip.groups</field>
+        </record>
+
+    </data>
+</openerp>