diff --git a/specs/stein/index.rst b/specs/stein/index.rst
index 2df8f5a..a4eb34d 100644
--- a/specs/stein/index.rst
+++ b/specs/stein/index.rst
@@ -9,3 +9,4 @@
email-notification-by-internal-tool
delete-message-with-claim-id
introduce-topic-resource-for-notification
+ remove-pool-group-totally
diff --git a/specs/stein/remove-pool-group-totally.rst b/specs/stein/remove-pool-group-totally.rst
new file mode 100644
index 0000000..44f94e2
--- /dev/null
+++ b/specs/stein/remove-pool-group-totally.rst
@@ -0,0 +1,371 @@
+..
+ This template should be in ReSTructured text. The filename in the git
+ repository should match the launchpad URL, for example a URL of
+ https://blueprints.launchpad.net/zaqar/+spec/awesome-thing should be named
+ awesome-thing.rst.
+
+ Please do not delete any of the sections in this
+ template. If you have nothing to say for a whole section, just write: None
+
+ For help with syntax, see http://sphinx-doc.org/rest.html
+ To test out your formatting, see http://www.tele3.cz/jbar/rest/rest.html
+
+===========================
+ remove-pool-group-totally
+===========================
+
+https://blueprints.launchpad.net/zaqar/+spec/remove-pool-group-totally
+
+remove-pool-group-totally.
+
+Problem description
+===================
+
+Currently pool group is used in pool and flavor resource, but the pool group
+only supports a 1:1 mapping with flavor. So it's not necessary to keep it
+since we can map 1 flavor : N pool directly. Another issue is currently there
+is no API to handle the pool group resource, which is very annoying to
+maintain by operators.
+
+For making a clarification to user, this bp proposes to remove useless
+pool group from Zaqar, just keeps the pool resource.
+
+For backward compatibility, we have split this work into two steps:
+
+1. In Queens, we have supported the old way to use pool_group and the new way
+ without it in Flavor both.
+
+2. In Stein, we will remove the pool_group totally and only keep the new way
+ in Flavor and Pool.
+
+This bp will implement the second step and totally remove the pool group from
+zaqar.
+
+
+Proposed change
+===============
+
+1. Modify pool and flavor operation API:
+
+ * Remove group from flavor operation API: like creat, update, show, list.
+ * Remove group from pool operation API: like creat, update, show, list.
+
+2. Remove the related logic codes about group in the zaqar server:
+
+3. The Data model of flavor and pool resources have been changed in Queens,
+ There is no need to discard pool_group field and Drop table PoolGroup
+ we will just keep it in table for degrade convenience.
+
+4. Modify the related logic codes about group in the zaqar client:
+
+ * openstack messaging flavor create
+ * openstack messaging flavor update
+ * openstack messaging pool create
+ * openstack messaging pool update
+
+
+Drawbacks
+---------
+None
+
+Alternatives
+------------
+None
+
+Data model impact
+-----------------
+None
+
+REST API impact
+---------------
+
+1. Create flavor API
+The Request JSON when create flavor::
+
+ PUT: /v2/flavors/{flavor_name}
+
+ {
+ "pool_list": [pool1, pool2]
+ }
+
+The response JSON when Create flavor::
+
+ Normal response codes: 201
+
+ Error response codes:
+ •BadRequest (400)
+ •Unauthorized (401)
+ •Forbidden (403)
+
+2. Update flavor API
+The Request JSON when update flavor::
+
+ PATCH: /v2/flavors/{flavor_name}
+
+ {
+ "pool_list": [pool1, pool2, pool3]
+ }
+
+The response JSON when update flavor::
+
+
+ {
+ "href": "/v2/flavors/testflavor",
+ "name": "testflavor",
+ "capabilities": [
+ "FIFO",
+ "CLAIMS",
+ "DURABILITY",
+ "AOD",
+ "HIGH_THROUGHPUT"
+ ],
+ "pool_list": [pool1, pool2, pool3]
+ }
+ Normal response codes: 200
+
+ Error response codes:
+ •BadRequest (400)
+ •Unauthorized (401)
+ •Forbidden (403)
+ •Not Found (404)
+ •ServiceUnavailable (503)
+
+3. Shows details for a flavor API
+The response JSON when show details flavor::
+
+ GET: /v2/flavors/{flavor_name}
+
+ {
+ "href": "/v2/flavors/testflavor",
+ "capabilities": [
+ "FIFO",
+ "CLAIMS",
+ "DURABILITY",
+ "AOD",
+ "HIGH_THROUGHPUT"
+ ],
+ "pool_list": [pool1, pool2],
+ "name": "testflavor"
+ }
+
+The response JSON when show details flavor::
+
+ Normal response codes: 200
+
+ Error response codes:
+ •BadRequest (400)
+ •Unauthorized (401)
+ •Forbidden (403)
+ •Not Found (404)
+ •ServiceUnavailable (503)
+
+4. List flavor API
+The response JSON when list flavors::
+
+ GET: /v2/flavors
+
+ {
+ "flavors": [
+ {
+ "href": "/v2/flavors/test_flavor1",
+ "name": "test_flavor1",
+ "pool_list": [pool1, pool2]
+ },
+ {
+ "href": "/v2/flavors/test_flavor2",
+ "name": "test_flavor2",
+ "pool_list": [pool3, pool4]
+ }
+ ],
+ "links": [
+ {
+ "href": "/v2/flavors?marker=test_flavor2",
+ "rel": "next"
+ }
+ ]
+ }
+
+The response JSON when list flavors::
+
+ Normal response codes: 200
+
+ Error response codes:
+ •Unauthorized (401)
+ •Forbidden (403)
+
+
+5. Create pools API
+The Request JSON when create pools::
+
+ PUT: /v2/pools/{pool_name}
+
+ {
+ "weight": 100,
+ "uri": "mongodb://127.0.0.1:27017",
+ "options":{
+ "max_retry_sleep": 1
+ },
+ "flavor": "testflavor"
+ }
+
+
+The response JSON when Create pools::
+
+ Normal response codes: 201
+
+ Error response codes:
+ •BadRequest (400)
+ •Unauthorized (401)
+ ••Conflict (409)
+
+6. Update pools API
+The Request JSON when update pools::
+
+ PATCH: /v2/pools/{pool_name}
+
+ {
+ "weight": 60,
+ "uri": "mongodb://127.0.0.1:27017",
+ "options":{
+ "max_retry_sleep": 1
+ },
+ "flavor": "testflavor1"
+ }
+
+The response JSON when update pools::
+
+
+ {
+ "href": "/v2/pools/test_pool",
+ "name": "test_pool",
+ "weight": 60,
+ "uri": "mongodb://127.0.0.1:27017",
+ "flavor": "testflavor1"
+ }
+ Normal response codes: 200
+
+ Error response codes:
+ •BadRequest (400)
+ •Unauthorized (401)
+ •Not Found (404)
+ •ServiceUnavailable (503)
+
+7. Shows details for a pool API
+The response JSON when show details pool::
+
+ GET: /v2/pools/{pool_name}
+
+ {
+ "href": "/v2/pools/test_pool",
+ "flavor": "flavor1",
+ "name": "test_pool",
+ "weight": 100,
+ "uri": "mongodb://127.0.0.1:27017"
+ }
+
+The response JSON when show details pool::
+
+ Normal response codes: 200
+
+ Error response codes:
+ •BadRequest (400)
+ •Unauthorized (401)
+ •ServiceUnavailable (503)
+
+8. List pools API
+The response JSON when list pools::
+
+ GET: /v2/pools
+
+ {
+ "pools": [
+ {
+ "href": "/v2/pools/test_pool1",
+ "flavor": "flavor1",
+ "name": "test_pool1",
+ "weight": 60,
+ "uri": "mongodb://192.168.1.10:27017"
+ },
+ {
+ "href": "/v2/pools/test_pool2",
+ "flavor": "flavor1",
+ "name": "test_pool2",
+ "weight": 40,
+ "uri": "mongodb://192.168.1.20:27017"
+ }
+ ],
+ "links": [
+ {
+ "href": "/v2/pools?marker=test_pool2",
+ "rel": "next"
+ }
+ ]
+ }
+
+The response JSON when list pools::
+
+ Normal response codes: 200
+
+ Error response codes:
+ •Unauthorized (401)
+ •Not Found (404)
+
+
+We use the v2 interface, just add pool_list in the flavor API and add the
+flavor in the pool API. we will remove the old way in this bp.
+
+#. Old Way:
+
+ * configure group in pool API and in flavor API;
+
+#. New Way:
+
+ * configure pool_list in flavor API
+ * add a pool to flavor:
+
+ #. method one: update pool_list in flavor API
+ #. method two: config a pool with the flavor in pool API.
+
+
+Implementation
+==============
+
+Assignee(s)
+-----------
+
+Primary assignee:
+ gecong<ge.cong@zte.com.cn>
+
+Milestones
+----------
+
+Target Milestone for completion:
+ Stein
+
+Work Items
+----------
+
+#. Modify pool and flavor operation APIs.
+#. Remove the related logic codes about group in the zaqar server.
+
+Dependencies
+============
+
+None
+
+Testing
+=======
+
+Both unit and Tempest tests need to be created to cover the code change.
+
+
+Documentation Impact
+====================
+
+The Zaqar API documentation will need to be updated to reflect the REST
+API changes.
+
+References
+==========
+None
+