diff --git a/addons/calendar/views/mail_activity_views.xml b/addons/calendar/views/mail_activity_views.xml
index cacdbe408f2..53be74a3b91 100644
--- a/addons/calendar/views/mail_activity_views.xml
+++ b/addons/calendar/views/mail_activity_views.xml
@@ -13,7 +13,7 @@
                   <attribute name="attrs">{'invisible': [('activity_category', '=', 'meeting')]}</attribute>
             </xpath>
             <xpath expr="//button[@name='action_close_dialog']" position="attributes">
-                  <attribute name="attrs">{'invisible': [('activity_category', '=', 'meeting')]}</attribute>
+                  <attribute name="attrs">{'invisible': ['|', ('activity_category', '=', 'meeting'), ('id', '!=', False)]}</attribute>
             </xpath>
             <xpath expr="//button[@name='action_done']" position="attributes">
                   <attribute name="attrs">{'invisible': ['|', ('activity_category', '=', 'meeting'), ('force_next', '=', True)]}</attribute>
diff --git a/addons/mail/data/mail_activity_data.xml b/addons/mail/data/mail_activity_data.xml
index f05d7695ec1..f3594e44fc2 100644
--- a/addons/mail/data/mail_activity_data.xml
+++ b/addons/mail/data/mail_activity_data.xml
@@ -11,17 +11,20 @@
             <field name="icon">fa-phone</field>
             <field name="delay_count">2</field>
             <field name="sequence">6</field>
+            <field name="is_master_data">True</field>
         </record>
         <record id="mail_activity_data_meeting" model="mail.activity.type">
             <field name="name">Meeting</field>
             <field name="icon">fa-users</field>
             <field name="sequence">9</field>
+            <field name="is_master_data">True</field>
         </record>
         <record id="mail_activity_data_todo" model="mail.activity.type">
             <field name="name">To Do</field>
             <field name="icon">fa-tasks</field>
             <field name="delay_count">5</field>
             <field name="sequence">12</field>
+            <field name="is_master_data">True</field>
         </record>
         <record id="mail_activity_data_upload_document" model="mail.activity.type">
             <field name="name">Upload Document</field>
@@ -36,6 +39,7 @@
             <field name="delay_count">0</field>
             <field name="sequence">99</field>
             <field name="decoration_type">warning</field>
+            <field name="is_master_data">True</field>
         </record>
     </data>
 </odoo>
diff --git a/addons/mail/models/mail_activity.py b/addons/mail/models/mail_activity.py
index 9d9a5d06b2f..0a58ef5aa88 100644
--- a/addons/mail/models/mail_activity.py
+++ b/addons/mail/models/mail_activity.py
@@ -33,12 +33,12 @@ class MailActivityType(models.Model):
         return super(MailActivityType, self).default_get(fields)
 
     name = fields.Char('Name', required=True, translate=True)
-    summary = fields.Char('Summary', translate=True)
+    summary = fields.Char('Default Summary', translate=True)
     sequence = fields.Integer('Sequence', default=10)
     active = fields.Boolean(default=True)
     create_uid = fields.Many2one('res.users', index=True)
     delay_count = fields.Integer(
-        'After', default=0, oldname='days',
+        'Scheduled Date', default=0, oldname='days',
         help='Number of days/week/month before executing the action. It allows to plan the action deadline.')
     delay_unit = fields.Selection([
         ('days', 'days'),
@@ -59,7 +59,7 @@ class MailActivityType(models.Model):
              ' and not available when managing activities for other models.')
     default_next_type_id = fields.Many2one('mail.activity.type', 'Default Next Activity',
         domain="['|', ('res_model_id', '=', False), ('res_model_id', '=', res_model_id)]")
-    force_next = fields.Boolean("Auto Schedule Next Activity", default=False)
+    force_next = fields.Boolean("Trigger Next Activity", default=False)
     next_type_ids = fields.Many2many(
         'mail.activity.type', 'mail_activity_rel', 'activity_id', 'recommended_id',
         domain="['|', ('res_model_id', '=', False), ('res_model_id', '=', res_model_id)]",
@@ -69,7 +69,7 @@ class MailActivityType(models.Model):
         domain="['|', ('res_model_id', '=', False), ('res_model_id', '=', res_model_id)]",
         string='Preceding Activities')
     category = fields.Selection([
-        ('default', 'Other'), ('upload_file', 'Upload Document')
+        ('default', 'Standard'), ('upload_file', 'Upload Document')
     ], default='default', string='Category',
         help='Categories may trigger specific behavior like opening calendar view or automatically mark as done when a document is uploaded')
     mail_template_ids = fields.Many2many('mail.template', string='Mails templates')
@@ -78,6 +78,7 @@ class MailActivityType(models.Model):
     initial_res_model_id = fields.Many2one('ir.model', 'Initial model', compute="_compute_initial_res_model_id", store=False,
             help='Technical field to keep trace of the model at the beginning of the edition for UX related behaviour')
     res_model_change = fields.Boolean(string="Model has change", help="Technical field for UX related behaviour", default=False, store=False)
+    is_master_data = fields.Boolean(string="Master data", help="This field is used to prevent master data from the deletion.")
 
     @api.onchange('res_model_id')
     def _onchange_res_model_id(self):
@@ -88,6 +89,13 @@ class MailActivityType(models.Model):
         for activity_type in self:
             activity_type.initial_res_model_id = activity_type.res_model_id
 
+    @api.multi
+    def unlink(self):
+        for activity_type in self:
+            if activity_type.is_master_data:
+                raise exceptions.ValidationError("You can not delete activity type that are used as master data.")
+        return super(MailActivityType, self).unlink()
+
 
 class MailActivity(models.Model):
     """ An actual activity to perform. Activities are linked to
@@ -120,7 +128,7 @@ class MailActivity(models.Model):
         help="Display name of the related document.", readonly=True)
     # activity
     activity_type_id = fields.Many2one(
-        'mail.activity.type', 'Activity',
+        'mail.activity.type', string='Activity Type',
         domain="['|', ('res_model_id', '=', False), ('res_model_id', '=', res_model_id)]", ondelete='restrict')
     activity_category = fields.Selection(related='activity_type_id.category', readonly=False)
     activity_decoration = fields.Selection(related='activity_type_id.decoration_type', readonly=False)
diff --git a/addons/mail/static/src/js/activity.js b/addons/mail/static/src/js/activity.js
index a0cb23b940d..5cb82f3f4de 100644
--- a/addons/mail/static/src/js/activity.js
+++ b/addons/mail/static/src/js/activity.js
@@ -214,6 +214,7 @@ var BasicActivity = AbstractField.extend({
     _openActivityForm: function (id, callback) {
         var action = {
             type: 'ir.actions.act_window',
+            name: _t("Schedule Activity"),
             res_model: 'mail.activity',
             view_mode: 'form',
             view_type: 'form',
diff --git a/addons/mail/static/tests/chatter_tests.js b/addons/mail/static/tests/chatter_tests.js
index 63f4f3bf53d..e75157d3ad7 100644
--- a/addons/mail/static/tests/chatter_tests.js
+++ b/addons/mail/static/tests/chatter_tests.js
@@ -1832,6 +1832,7 @@ QUnit.test('form activity widget: edit next activity', function (assert) {
                       default_res_id: 2,
                       default_res_model: "partner"
                     },
+                    name: "Schedule Activity",
                     res_id: 1,
                     res_model: "mail.activity",
                     target: "new",
diff --git a/addons/mail/views/mail_activity_views.xml b/addons/mail/views/mail_activity_views.xml
index 8bca8e907b3..0ee562df52e 100644
--- a/addons/mail/views/mail_activity_views.xml
+++ b/addons/mail/views/mail_activity_views.xml
@@ -32,6 +32,7 @@
                                 </div>
                                 <field name="delay_from"/>
                             </div>
+                            <field name="is_master_data" groups="base.group_no_one"/>
                         </group>
                         <group name="activity_planning">
                             <field name="force_next"/>
@@ -127,8 +128,11 @@
                     </group>
                     <field name="note" placeholder="Log a note..."/>
                     <footer>
-                        <button string="Schedule" name="action_close_dialog"
-                            type="object" class="btn-primary"/>
+                        <field name="id" invisible="1"/>
+                        <button string="Schedule" name="action_close_dialog" type="object" class="btn-primary"
+                            attrs="{'invisible': [('id', '!=', False)]}"/>
+                        <button string="Save" name="action_close_dialog" type="object" class="btn-primary"
+                            attrs="{'invisible': [('id', '=', False)]}"/>
                         <button attrs="{'invisible': [('force_next', '=', True)]}" string="Mark as Done" name="action_done"
                             type="object" class="btn-secondary"
                             context="{'mail_activity_quick_update': True}"/>