diff --git a/time_tracker_api/activities/activities_api.py b/time_tracker_api/activities/activities_api.py
index b9578842..9a5ab4ee 100644
--- a/time_tracker_api/activities/activities_api.py
+++ b/time_tracker_api/activities/activities_api.py
@@ -4,28 +4,56 @@
 
 # Activity Model
 activity = ns.model('Activity', {
-    'id': fields.String(readOnly=True, required=True, title='Identifier',
-                         description='The unique id of the activity'),
-    'name': fields.String(required=True, title='Name', max_length=50,
-                          description='Canonical name of the activity'),
-    'description': fields.String(title='Description',
-                                 description='Comments about the activity'),
-    'tenant_id': fields.String(required=True, title='Tenant', max_length=64,
-                               description='The tenant this belongs to')
+    'name': fields.String(
+        required=True,
+        title='Name',
+        max_length=50,
+        description='Canonical name of the activity',
+    ),
+    'description': fields.String(
+        title='Description',
+        description='Comments about the activity',
+    ),
+})
+
+activity_response = ns.inherit('ActivityResponse', activity, {
+    'id': fields.String(
+        readOnly=True,
+        required=True,
+        title='Identifier',
+        description='The unique identifier',
+    ),
+    'created_at': fields.Date(
+        readOnly=True,
+        title='Created',
+        description='Date of creation'
+    ),
+    'created_by': fields.String(
+        readOnly=True,
+        title='Creator',
+        max_length=64,
+        description='User that created it',
+    ),
+    'tenant_id': fields.String(
+        readOnly=True,
+        title='Tenant',
+        max_length=64,
+        description='The tenant this belongs to',
+    ),
 })
 
 
-@ns.route('/')
+@ns.route('')
 class Activities(Resource):
     @ns.doc('list_activities')
-    @ns.marshal_list_with(activity, code=200)
+    @ns.marshal_list_with(activity_response, code=200)
     def get(self):
         """List all available activities"""
         return []
 
     @ns.doc('create_activity')
     @ns.expect(activity)
-    @ns.marshal_with(activity, code=201)
+    @ns.marshal_with(activity_response, code=201)
     @ns.response(400, 'Invalid format of the attributes of the activity.')
     def post(self):
         """Create a single activity"""
@@ -37,7 +65,7 @@ def post(self):
 @ns.param('id', 'The unique identifier of the activity')
 class Activity(Resource):
     @ns.doc('get_activity')
-    @ns.marshal_with(activity)
+    @ns.marshal_with(activity_response)
     def get(self, id):
         """Retrieve all the data of a single activity"""
         return {}
@@ -51,7 +79,7 @@ def delete(self, id):
     @ns.doc('put_activity')
     @ns.response(400, 'Invalid format of the attributes of the activity.')
     @ns.expect(activity)
-    @ns.marshal_with(activity)
+    @ns.marshal_with(activity_response)
     def put(self, id):
         """Updates an activity"""
         return ns.payload
diff --git a/time_tracker_api/api.py b/time_tracker_api/api.py
index 4f2742fa..8fbd74d7 100644
--- a/time_tracker_api/api.py
+++ b/time_tracker_api/api.py
@@ -10,3 +10,6 @@
 
 from time_tracker_api.activities import activities_api
 api.add_namespace(activities_api.ns)
+
+from time_tracker_api.time_entries import time_entry_api
+api.add_namespace(time_entry_api.ns)
diff --git a/time_tracker_api/time_entries/time_entry_api.py b/time_tracker_api/time_entries/time_entry_api.py
new file mode 100644
index 00000000..95434da4
--- /dev/null
+++ b/time_tracker_api/time_entries/time_entry_api.py
@@ -0,0 +1,134 @@
+from flask_restplus import fields, Resource, Namespace
+
+ns = Namespace('time-entries', description='API for time entries')
+
+# TimeEntry Model
+time_entry = ns.model('TimeEntry', {
+    'project_id': fields.String(
+        required=True,
+        title='Project',
+        max_length=64,
+        description='The id of the selected project',
+    ),
+    'activity_id': fields.String(
+        required=False,
+        title='Activity',
+        max_length=64,
+        description='The id of the selected activity',
+    ),
+    'technologies': fields.String(
+        required=True,
+        title='Technologies',
+        max_length=64,
+        description='Canonical names of the used technologies during this period',
+    ),
+    'description': fields.String(
+        title='Comments',
+        description='Comments about the time entry'
+    ),
+    'start_date': fields.DateTime(
+        required=True,
+        title='Start date',
+        description='When the user started doing this activity',
+    ),
+    'end_date': fields.DateTime(
+        required=True,
+        title='End date',
+        description='When the user ended doing this activity',
+    ),
+})
+
+time_entry_response = ns.inherit('TimeEntryResponse', time_entry, {
+    'id': fields.String(
+        readOnly=True,
+        required=True,
+        title='Identifier',
+        description='The unique identifier',
+    ),
+    'running': fields.Boolean(
+        readOnly=True,
+        title='Is it running?',
+        description='Whether this time entry is currently running or not'
+    ),
+    'created_at': fields.Date(
+        readOnly=True,
+        title='Created',
+        description='Date of creation'
+    ),
+    'created_by': fields.String(
+        readOnly=True,
+        title='Creator',
+        max_length=64,
+        description='User that created it',
+    ),
+    'tenant_id': fields.String(
+        readOnly=True,
+        title='Tenant',
+        max_length=64,
+        description='The tenant this belongs to',
+    ),
+})
+
+
+@ns.route('')
+class TimeEntries(Resource):
+    @ns.doc('list_time_entries')
+    @ns.marshal_list_with(time_entry_response, code=200)
+    def get(self):
+        """List all available time entries"""
+        return []
+
+    @ns.doc('create_time_entry')
+    @ns.expect(time_entry)
+    @ns.marshal_with(time_entry_response, code=201)
+    @ns.response(400, 'Invalid format of the attributes of the time entry')
+    def post(self):
+        """Starts a time entry by creating it"""
+        return ns.payload, 201
+
+
+@ns.route('/<string:id>')
+@ns.response(404, 'Time entry not found')
+@ns.param('id', 'The unique identifier of the time entry')
+class TimeEntry(Resource):
+    @ns.doc('get_time_entry')
+    @ns.marshal_with(time_entry_response)
+    def get(self, id):
+        """Retrieve all the data of a single time entry"""
+        return {}
+
+    @ns.doc('delete_time_entry')
+    @ns.response(204, 'The time entry was deleted successfully (No content is returned)')
+    def delete(self, id):
+        """Deletes a time entry"""
+        return None, 204
+
+    @ns.doc('put_time_entry')
+    @ns.response(400, 'Invalid format of the attributes of the time entry.')
+    @ns.expect(time_entry)
+    @ns.marshal_with(time_entry_response)
+    def put(self, id):
+        """Updates a time entry"""
+        return ns.payload
+
+
+@ns.route('<string:id>/stop')
+@ns.response(404, 'Running time entry not found')
+@ns.param('id', 'The unique identifier of a running time entry')
+class StopTimeEntry(Resource):
+    @ns.doc('stop_time_entry')
+    @ns.response(204, 'The time entry was stopped successfully (No content is returned)')
+    def post(self, id):
+        """Stops a running time entry"""
+        return None, 204
+
+
+@ns.route('<string:id>/continue')
+@ns.response(404, 'Stopped time entry not found')
+@ns.param('id', 'The unique identifier of a stopped time entry')
+class ContinueTimeEntry(Resource):
+    @ns.doc('continue_time_entry')
+    @ns.response(204, 'The time entry was continued successfully (No content is returned)')
+    def post(self, id):
+        """Restart an stopped time entry"""
+        return None, 204