diff --git a/specs/train/rabbitmq-driver-threads.rst b/specs/train/rabbitmq-driver-threads.rst
new file mode 100644
index 0000000..d4f4cb1
--- /dev/null
+++ b/specs/train/rabbitmq-driver-threads.rst
@@ -0,0 +1,151 @@
+==============================================================================
+Allow customer to choose to use std threads or greenthreads in rabbitmq driver
+==============================================================================
+
+https://blueprints.launchpad.net/oslo.messaging/+spec/rabbitmq-driver-threads
+
+oslo.messaging RabbitMq driver use greenthreads from eventlet. In some use case
+it can be useful to also can use python standard threads. This allow customers
+design that they need exactly in their context. This specification proposes
+changes to adapt the rabbitmq driver to provide mechanismes needed to lets
+customers choice between eventlet greenthreads or python standard threads.
+
+Problem description
+===================
+
+The rabbitmq driver is commonly used to healt check the AMQP connections with
+rabbitmq to ensure connections by using the driver heartbeat mechanism.
+
+The AMQP heartbeat can be used in mod_wsgi. the threading library is
+monkey_patched by eventlet, and it's not compatible with mod_wsgi.
+
+Indeed, mod_wsgi stops the execution of its embedded interpreter, the
+AMQP heartbeat thread can't be resumed until there's a message to be
+processed in the mod_wsgi queue, which would resume the python
+interpreter and make eventlet resume the thread.
+
+Allow customers to use standard threads and disabling eventlet will fix
+this kind of issues.
+
+Proposed change
+===============
+
+The spec proposes to introduce a new configuration option who lets customers
+choose the threading mode to use. By default we'll keep the eventlet mode
+with the monkey patched threading module, and user by using configuration
+will can choose to turn off the eventlet mode and to use the non monkey
+patched mode.
+
+The ``eventlet_mode`` config option will be introduced, with the default value
+defined to turned on (``on``).
+
+User can choose to set this value to ``off`` to turn off the eventlet mode
+and using python standard threads.
+
+This option will have a default value so doesn't need to update existing
+usages. Also the existing usages of this driver will continue to have the
+same behaviors if nobody changes the configuration explicitely so it's
+transparent for end users.
+
+Here is a example that describes the introduced option turned off::
+
+    [oslo_messaging_rabbit]
+    eventlet_mode = off
+
+
+Alternatives
+------------
+
+Remove eventlet on the rabbitmq driver and prefer to use possible alternatives
+like using futurist.
+
+Impact on Existing usages
+-------------------------
+
+No impact on the existing usages since the default behavior will continue
+to use eventlet by default (``eventlet_mode=on``).
+
+Security impact
+---------------
+
+There's a slim chance that driver behavior could change if pre-existing
+environment variables are present that happen to match the new option
+name described here.
+
+Performance Impact
+------------------
+
+No significant performance impact is expected.
+
+Configuration Impact
+--------------------
+
+A new option will be added that can impact users in some unidentified
+scenarios.
+
+Developer Impact
+----------------
+
+Developers will have an additional customization option available.
+
+Testing Impact
+--------------
+
+Additional unit tests will be required to cover the added functionality.
+
+Implementation
+==============
+
+Assignee(s)
+-----------
+
+Primary assignee:
+  hberaud
+
+Other contributors:
+  volunteers?
+
+Milestones
+----------
+
+..TODO(hberaud): figure this out
+
+Work Items
+----------
+
+* Implement the described modes in rabbitmq driver.
+* Update documentation.
+* Update the sample configuration generator to include the variable names.
+* Update the documentation generator to include the variable names.
+
+
+Incubation
+==========
+
+N/A
+
+Documentation Impact
+====================
+
+The documentation will need to be updated to indicate the option can be
+overridden with an environment variable and to describe how the described
+modes works.
+
+Dependencies
+============
+
+N/A
+
+References
+==========
+
+* Eventlet Best Practices:
+  `https://review.opendev.org/#/c/154642/`_
+* Related discussion on the ML about mod_wsgi and monkey patch:
+  `http://lists.openstack.org/pipermail/openstack-discuss/2019-April/005305.html`_
+
+.. note::
+
+  This work is licensed under a Creative Commons Attribution 3.0
+  Unported License.
+  http://creativecommons.org/licenses/by/3.0/legalcode