diff --git a/addons/hr_timesheet/project_timesheet.py b/addons/hr_timesheet/project_timesheet.py
index 83834341060..6d733de6af8 100644
--- a/addons/hr_timesheet/project_timesheet.py
+++ b/addons/hr_timesheet/project_timesheet.py
@@ -2,6 +2,18 @@
 # Part of Odoo. See LICENSE file for full copyright and licensing details.
 
 from openerp.osv import fields, osv
+from openerp import tools
+
+
+class project_project(osv.osv):
+    _inherit = 'project.project'
+
+    _columns = {
+        'subtask_project_id': fields.many2one(
+            'project.project', string='Sub-task Project',
+            help="Choosing a sub-tasks project will both enable sub-tasks and set their default project (possibly the project itself)",
+            ondelete="restrict"),
+    }
 
 
 class task(osv.osv):
@@ -9,28 +21,63 @@ class task(osv.osv):
 
     # Compute: effective_hours, total_hours, progress
     def _hours_get(self, cr, uid, ids, field_names, args, context=None):
+        def _get_child_hour(child, res):
+            if child.stage_id and child.stage_id.fold:
+                return res[child.id]['effective_hours'] + res[child.id]['children_hours']
+            else:
+                return max(child.planned_hours, res[child.id]['effective_hours'] + res[child.id]['children_hours'])
+
         res = {}
-        for task in self.browse(cr, uid, ids, context=context):
-            res[task.id] = {'effective_hours': 0.0, 'remaining_hours': task.planned_hours, 'progress': 0.0, 'total_hours': task.planned_hours, 'delay_hours': 0.0}
-        tasks_data = self.pool['account.analytic.line'].read_group(cr, uid, [('task_id', 'in', ids)], ['task_id','unit_amount'], ['task_id'], context=context)
-        for data in tasks_data:
-            task = self.browse(cr, uid, data['task_id'][0], context=context)
-            res[data['task_id'][0]] = {'effective_hours': data.get('unit_amount', 0.0), 'remaining_hours': task.planned_hours - data.get('unit_amount', 0.0)}
-            res[data['task_id'][0]]['total_hours'] = res[data['task_id'][0]]['remaining_hours'] + data.get('unit_amount', 0.0)
-            res[data['task_id'][0]]['delay_hours'] = res[data['task_id'][0]]['total_hours'] - task.planned_hours
-            res[data['task_id'][0]]['progress'] = 0.0
-            if (task.planned_hours > 0.0 and data.get('unit_amount', 0.0)):
-                res[data['task_id'][0]]['progress'] = round(min(100.0 * data.get('unit_amount', 0.0) / task.planned_hours, 99.99),2)
+        task_to_read = self.search(cr, uid, [('id', 'child_of', ids)])
+        task_to_sort = {}
+        for task in self.browse(cr, uid, task_to_read, context=context):
+            res[task.id] = {
+                'effective_hours': 0.0,
+                'remaining_hours': task.planned_hours,
+                'progress': 0.0,
+                'total_hours': task.planned_hours,
+                'delay_hours': 0.0,
+                'children_hours' : 0.0
+            }
+            task_to_sort[task.id] = [child.id for child in task.child_ids]
+
+        tasks_data = self.pool['account.analytic.line'].read_group(
+            cr, uid, [('task_id', 'in', task_to_read)], ['task_id','unit_amount'], ['task_id'], context=context)
+        tasks_data_dict = {data['task_id'][0] : data for data in tasks_data}
+        for task_id in tools.topological_sort(task_to_sort):
+            task = self.browse(cr, uid, task_id, context=context)
+            values = {
+                'effective_hours': tasks_data_dict.get(task_id, {}).get('unit_amount', 0.0),
+                'children_hours' : sum([_get_child_hour(child, res) for child in task.child_ids])
+            }
+            values['remaining_hours'] = task.planned_hours - values['effective_hours'] - values['children_hours']
+            values['total_hours'] = values['remaining_hours'] + values['effective_hours']
+            values['delay_hours'] = values['total_hours'] - task.planned_hours
+            values['progress'] = 0.0
             # TDE CHECK: if task.state in ('done','cancelled'):
             if task.stage_id and task.stage_id.fold:
-                res[data['task_id'][0]]['progress'] = 100.0
+                values['progress'] = 100.0
+            elif task.planned_hours > 0.0:
+                values['progress'] = round(min(100.0 * (values['effective_hours'] + values['children_hours']) / task.planned_hours, 99.99),2)
+            res[task.id] = values
+        return {k : val for k, val in res.iteritems() if k in ids} #Filter only needed result
+
+    def _get_subtask_count(self, cr, uid, ids, field_names, args, context=None):
+        res = dict.fromkeys(ids, 0)
+        for task_id in ids:
+            res[task_id] = (self.search_count(
+                cr, uid, [('id', 'child_of', task_id)], context=context) - 1) # don't count task itself
         return res
 
-    def _get_task(self, cr, uid, id, context=None):
+    def _get_task(self, cr, uid, ids, context=None):
         res = []
-        for line in self.pool.get('account.analytic.line').search_read(cr,uid,[('task_id', '!=', False),('id','in',id)], context=context):
+        for line in self.pool['account.analytic.line'].search_read(
+                cr, uid, [('task_id', '!=', False), ('id', 'in', ids)], context=context):
             res.append(line['task_id'][0])
-        return res
+        return self.pool['project.task'].search(cr, uid, [('id', 'parent_of', res)])
+
+    def _get_parent_tasks(self, cr, uid, ids, context=None):
+        return self.pool['project.task'].search(cr, uid, [('id', 'parent_of', ids)])
 
     def _get_total_hours(self):
         return super(task, self)._get_total_hours() + self.effective_hours
@@ -38,32 +85,44 @@ class task(osv.osv):
     _columns = {
         'remaining_hours': fields.function(_hours_get, string='Remaining Hours', multi='line_id', help="Total remaining time, can be re-estimated periodically by the assignee of the task.",
             store = {
-                'project.task': (lambda self, cr, uid, ids, c={}: ids, ['timesheet_ids', 'remaining_hours', 'planned_hours'], 10),
+                'project.task': (_get_parent_tasks, ['timesheet_ids', 'remaining_hours', 'planned_hours', 'parent_id', 'stage_id'], 10),
+                'account.analytic.line': (_get_task, ['task_id', 'unit_amount'], 10),
+            }),
+        'children_hours': fields.function(_hours_get, string='Sub-tasks Hours', type='float', multi='line_id',
+            help="Sum of the planned hours of all sub-tasks (when a sub-task is closed or its spent hours exceed its planned hours, spent hours are counted instead)",
+            store = {
+                'project.task': (_get_parent_tasks, ['timesheet_ids', 'remaining_hours', 'planned_hours', 'parent_id', 'stage_id'], 10),
                 'account.analytic.line': (_get_task, ['task_id', 'unit_amount'], 10),
             }),
         'effective_hours': fields.function(_hours_get, string='Hours Spent', multi='line_id', help="Computed using the sum of the task work done.",
             store = {
-                'project.task': (lambda self, cr, uid, ids, c={}: ids, ['timesheet_ids', 'remaining_hours', 'planned_hours'], 10),
+                'project.task': (_get_parent_tasks, ['timesheet_ids', 'remaining_hours', 'planned_hours', 'parent_id', 'stage_id'], 10),
                 'account.analytic.line': (_get_task, ['task_id', 'unit_amount'], 10),
             }),
         'total_hours': fields.function(_hours_get, string='Total', multi='line_id', help="Computed as: Time Spent + Remaining Time.",
             store = {
-                'project.task': (lambda self, cr, uid, ids, c={}: ids, ['timesheet_ids', 'remaining_hours', 'planned_hours'], 10),
+                'project.task': (_get_parent_tasks, ['timesheet_ids', 'remaining_hours', 'planned_hours', 'parent_id', 'stage_id'], 10),
                 'account.analytic.line': (_get_task, ['task_id', 'unit_amount'], 10),
             }),
-        'progress': fields.function(_hours_get, string='Progress (%)', multi='line_id', group_operator="avg", help="If the task has a progress of 99.99% you should close the task if it's finished or reevaluate the time",
+        'progress': fields.function(_hours_get, string='Working Time Progress (%)', multi='line_id', group_operator="avg", help="If the task has a progress of 99.99% you should close the task if it's finished or reevaluate the time",
             store = {
-                'project.task': (lambda self, cr, uid, ids, c={}: ids, ['timesheet_ids', 'remaining_hours', 'planned_hours', 'state', 'stage_id'], 10),
+                'project.task': (_get_parent_tasks, ['timesheet_ids', 'remaining_hours', 'planned_hours', 'parent_id', 'state', 'stage_id'], 10),
                 'account.analytic.line': (_get_task, ['task_id', 'unit_amount'], 10),
             }),
         'delay_hours': fields.function(_hours_get, string='Delay Hours', multi='line_id', help="Computed as difference between planned hours by the project manager and the total hours of the task.",
             store = {
-                'project.task': (lambda self, cr, uid, ids, c={}: ids, ['timesheet_ids', 'remaining_hours', 'planned_hours'], 10),
+                'project.task': (_get_parent_tasks, ['timesheet_ids', 'remaining_hours', 'planned_hours','parent_id', 'stage_id'], 10),
                 'account.analytic.line': (_get_task, ['task_id', 'unit_amount'], 10),
-            }),
+           }),
         'timesheet_ids': fields.one2many('account.analytic.line', 'task_id', 'Timesheets'),
+        'parent_id' : fields.many2one('project.task', string='Parent Task', select=True),
+        'child_ids' : fields.one2many('project.task', 'parent_id', string="Sub-tasks"),
+        'subtask_project_id': fields.related('project_id', 'subtask_project_id',  type='many2one', relation='project.project', string='Sub-task Project'),
+        'subtask_count' : fields.function(_get_subtask_count, type='integer', string="Sub-task count"),
     }
 
     _defaults = {
         'progress': 0,
     }
+
+    _constraints = [(osv.osv._check_recursion, 'Circular references are not permitted between tasks and sub-tasks', ['parent_id'])]
diff --git a/addons/hr_timesheet/project_timesheet_view.xml b/addons/hr_timesheet/project_timesheet_view.xml
index 2118bb19432..300b61ae44c 100644
--- a/addons/hr_timesheet/project_timesheet_view.xml
+++ b/addons/hr_timesheet/project_timesheet_view.xml
@@ -28,21 +28,52 @@
                 <div name="button_box" position="inside">
                     <button class="oe_stat_button" name="%(act_hr_timesheet_line_by_project)d" type="action" icon="fa-calendar" string="Timesheets"/>
                 </div>
+                <field name="user_id" position="after">
+                    <field name="subtask_project_id" groups="base.group_no_one" />
+                </field>
             </field>
         </record>
 
+        <record id="act_project_task_sub_task" model="ir.actions.act_window">
+            <field name="name">Sub-tasks</field>
+            <field name="res_model">project.task</field>
+            <field name="view_mode">kanban,tree,form,calendar,pivot,graph</field>
+            <field name="domain">[('id', 'child_of', active_id), ('id', '!=', active_id)]</field>
+            <field name="context">
+            {
+                'default_parent_id' : active_id,
+                'default_project_id' : project_id,
+                'default_name' : name + ':',
+                'default_partner_id' : partner_id,
+            }
+            </field>
+            <field name="search_view_id" ref="project.view_task_search_form"/>
+        </record>
+
         <record model="ir.ui.view" id="view_task_form2_inherited">
             <field name="name">project.task.form.inherited</field>
             <field name="model">project.task</field>
             <field name="inherit_id" ref="project.view_task_form2" />
             <field name="groups_id" eval="[(4, ref('base.group_user'))]"/>
             <field name="arch" type="xml">
+                <button name="toggle_active" position="after">
+                    <button name="%(act_project_task_sub_task)d" type="action" class="oe_stat_button" icon="fa-tasks"
+                            attrs="{'invisible' : [('subtask_project_id', '=', False)]}"
+                            context="{'project_id': subtask_project_id, 'name': name, 'partner_id': partner_id}" >
+                        <field string="Sub-tasks" name="subtask_count" widget="statinfo"/>
+                    </button>
+                </button>
                 <field name="tag_ids" position="after">
                     <field name="progress" widget="progressbar"/>
                 </field>
                 <field name="user_id" position="after">
                     <field name="planned_hours" widget="float_time" on_change="onchange_planned(planned_hours)"/>
                 </field>
+                <field name="partner_id" position="after">
+                    <field name="parent_id" attrs="{'invisible' : [('parent_id', '=', False)]}" />
+                    <field name="child_ids" invisible="1" />
+                    <field name="subtask_project_id" invisible="1" />
+                </field>
                 <xpath expr="//notebook/page[@name='description_page']" position="after">
                     <page string="Timesheets">
                     <field name="timesheet_ids" context="{'default_project_id': project_id}">
@@ -57,6 +88,7 @@
                     <group>
                      <group class="oe_subtotal_footer oe_right" name="project_hours">
                         <field name="effective_hours" widget="float_time" />
+                        <field name="children_hours" widget="float_time" attrs="{'invisible' : [('children_hours', '=', 0.0)]}" />
                         <field name="remaining_hours" widget="float_time" class="oe_subtotal_footer_separator" />
                      </group>
                     </group>
@@ -96,5 +128,26 @@
 
             </field>
         </record>
+
+        <record id="view_task_kanban_inherited_progress" model="ir.ui.view">
+            <field name="name">project.task.timesheet.kanban.inherited.progress</field>
+            <field name="model">project.task</field>
+            <field name="inherit_id" ref="project.view_task_kanban"/>
+            <field name="arch" type="xml">
+                <templates position="before">
+                    <field name="progress" />
+                    <field name="remaining_hours" />
+                </templates>
+                <div class="oe_kanban_bottom_left" position="inside">
+                   <t t-if="record.progress.raw_value &gt; 80 and record.progress.raw_value &lt; 100">
+                       <div t-att-class="'oe_kanban_align label label-' + (record.progress.raw_value &gt;= 99 ? 'danger': 'warning')"
+                             groups="project.group_time_work_estimation_tasks" title="Remaining hours">
+                              <field name="remaining_hours" widget="float_time" />
+                       </div>
+                   </t>
+                </div>
+             </field>
+         </record>
+
     </data>
 </openerp>
diff --git a/addons/project/project_view.xml b/addons/project/project_view.xml
index c0d331ec49b..b44e3850729 100644
--- a/addons/project/project_view.xml
+++ b/addons/project/project_view.xml
@@ -281,14 +281,14 @@
                             <div class="oe_clear"/>
                         </page>
                         <page string="Extra Info">
-                            <group col="4">
-                                <group col="2">
+                            <group>
+                                <group>
                                     <field name="sequence" groups="base.group_no_one"/>
                                     <field name="partner_id"/>
                                     <field name="company_id" groups="base.group_multi_company" options="{'no_create': True}"/>
                                     <field name="displayed_image_id" groups="base.group_no_one"/>
                                 </group>
-                                <group col="2">
+                                <group>
                                     <field name="date_assign" groups="base.group_no_one"/>
                                     <field name="date_last_stage_update" groups="base.group_no_one"/>
                                 </group>
diff --git a/addons/sale_service/models/sale_service.py b/addons/sale_service/models/sale_service.py
index bcaabaaf20e..e6343e940dc 100644
--- a/addons/sale_service/models/sale_service.py
+++ b/addons/sale_service/models/sale_service.py
@@ -118,6 +118,17 @@ class project_task(osv.osv):
             "context": {"create": False, "show_sale": True},
         }
 
+    def onchange_parent_id(self, cr, uid, ids, parent_id, context=None):
+        if not parent_id:
+            return {'value' : {'procurement_id': False, 'sale_line_id': False }}
+        parent_task = self.browse(cr, uid, parent_id, context=context)
+        return {
+            'value' : {
+                'procurement_id' : parent_task.procurement_id.id,
+                'sale_line_id' : parent_task.sale_line_id.id,
+            }
+        }
+
 
 class ProductProduct(models.Model):
     _inherit = 'product.product'
diff --git a/addons/sale_service/views/sale_service_view.xml b/addons/sale_service/views/sale_service_view.xml
index e097b02d92b..3a49020d835 100644
--- a/addons/sale_service/views/sale_service_view.xml
+++ b/addons/sale_service/views/sale_service_view.xml
@@ -37,8 +37,12 @@
                             string="Sales Order"/>
                 </xpath>
                 <field name="company_id" position="before">
+                    <field name="procurement_id" groups="base.group_no_one"/>
                     <field name="sale_line_id" string="Order Line" groups="base.group_no_one"/>
                 </field>
+                <field name="parent_id" position="attributes">
+                    <attribute name="on_change">onchange_parent_id(parent_id)</attribute>
+                </field>
             </field>
         </record>
         <record id="view_order_form_inherit_sale_service" model="ir.ui.view">
diff --git a/addons/web_kanban/static/src/less/kanban_view.less b/addons/web_kanban/static/src/less/kanban_view.less
index fbbcc92365f..ddd7f6374d1 100644
--- a/addons/web_kanban/static/src/less/kanban_view.less
+++ b/addons/web_kanban/static/src/less/kanban_view.less
@@ -96,6 +96,10 @@
 
         .oe_kanban_bottom_left {
             float: left;
+            .oe_kanban_align {
+                display: inline-block;
+                vertical-align: middle;
+            }
         }
 
         .o_kanban_tags {