diff --git a/sig-list.md b/sig-list.md
index ac4d15af8..88c42c25e 100644
--- a/sig-list.md
+++ b/sig-list.md
@@ -55,6 +55,7 @@ When the need arises, a [new SIG can be created](sig-creation-procedure.md)
 
 | Name | Organizers | Contact | Meetings |
 |------|------------|---------|----------|
+|[App Def](wg-app-def/README.md)|* [Antoine Legrand](https://github.com/ant31), CoreOS<br>* [Sebastien Goasguen](https://github.com/sebgoa), Bitnami<br>|* [Slack](https://kubernetes.slack.com/messages/wg-app-def)<br>* [Mailing List](https://groups.google.com/forum/#!forum/kubernetes-wg-app-def)|* [Wednesdays at 16:00 UTC (bi-weekly)]()<br>
 |[Container Identity](wg-container-identity/README.md)|* [Clayton Coleman](https://github.com/smarterclayton), Red Hat<br>* [Greg Gastle](https://github.com/destijl), Google<br>|* [Slack](https://kubernetes.slack.com/messages/wg-container-identity)<br>* [Mailing List](https://groups.google.com/forum/#!forum/kubernetes-wg-container-identity)|* [Tuesdays at 15:00 UTC (bi-weekly (On demand))](TBD)<br>
 |[Resource Management](wg-resource-management/README.md)|* [Vishnu Kannan](https://github.com/vishh), Google<br>* [Derek Carr](https://github.com/derekwaynecarr), Red Hat<br>|* [Slack](https://kubernetes.slack.com/messages/wg-resource-mgmt)<br>* [Mailing List](https://groups.google.com/forum/#!forum/kubernetes-wg-resource-management)|* [Wednesdays at 18:00 UTC (weekly (On demand))](https://zoom.us/j/4799874685)<br>
 |[cluster api](wg-cluster-api/README.md)|* [Kris Nova](https://github.com/kris-nova), Microsoft<br>* [Jacob Beacham](https://github.com/pipejakob), Google<br>* [Robert Bailey](https://github.com/roberthbailey), Google<br>|* [Slack](https://kubernetes.slack.com/messages/sig-cluster-lifecycle)<br>* [Mailing List](https://groups.google.com/forum/#!forum/kubernetes-sig-cluster-lifecycle)|
diff --git a/sigs.yaml b/sigs.yaml
index c676de6d0..b0022b7cc 100644
--- a/sigs.yaml
+++ b/sigs.yaml
@@ -779,3 +779,27 @@ workinggroups:
     contact:
       slack: sig-cluster-lifecycle
       mailing_list: https://groups.google.com/forum/#!forum/kubernetes-sig-cluster-lifecycle
+  - name: App Def
+    dir: wg-app-def
+    mission_statement: >
+      Improve UX of declarative primitives in the API and/or primary client libraries and tools,
+      understand the needs of other parts of the ecosystem on this layer, and improve the interoperability
+      of application management tools through better separation of concerns, common conventions,
+      and common principles.
+        
+      Charter can be found [here](https://docs.google.com/document/d/1TzRwzWYRulx4o8Fii8k7ToIx4LR4MSncxxLdJ9TkOAs/edit#)
+    leads:
+    - name: Antoine Legrand
+      github: ant31
+      company: CoreOS
+    - name: Sebastien Goasguen
+      github: sebgoa
+      company: Bitnami
+    meetings:
+    - day: Wednesday
+      utc: "16:00"
+      frequency: bi-weekly
+    meeting_archive_url: hhttps://docs.google.com/document/d/1Pxc-qwAt4FvuISZ_Ib5KdUwlynFkGueuzPx5Je_lbGM/edit
+    contact:
+      slack: wg-app-def
+      mailing_list: https://groups.google.com/forum/#!forum/kubernetes-wg-app-def
\ No newline at end of file
diff --git a/wg-app-def/README.md b/wg-app-def/README.md
new file mode 100644
index 000000000..ea70f289b
--- /dev/null
+++ b/wg-app-def/README.md
@@ -0,0 +1,31 @@
+<!---
+This is an autogenerated file!
+
+Please do not edit this file directly, but instead make changes to the
+sigs.yaml file in the project root.
+
+To understand how this file is generated, see generator/README.md.
+-->
+# App Def Working Group
+
+Improve UX of declarative primitives in the API and/or primary client libraries and tools, understand the needs of other parts of the ecosystem on this layer, and improve the interoperability of application management tools through better separation of concerns, common conventions, and common principles.
+  
+Charter can be found [here](https://docs.google.com/document/d/1TzRwzWYRulx4o8Fii8k7ToIx4LR4MSncxxLdJ9TkOAs/edit#)
+
+## Meetings
+* [Wednesdays at 16:00 UTC]() (bi-weekly). [Convert to your timezone](http://www.thetimezoneconverter.com/?t=16:00&tz=UTC).
+
+Meeting notes and Agenda can be found [here](hhttps://docs.google.com/document/d/1Pxc-qwAt4FvuISZ_Ib5KdUwlynFkGueuzPx5Je_lbGM/edit).
+Meeting recordings can be found [here]().
+
+## Organizers
+* Antoine Legrand (**[@ant31](https://github.com/ant31)**), CoreOS
+* Sebastien Goasguen (**[@sebgoa](https://github.com/sebgoa)**), Bitnami
+
+## Contact
+* [Slack](https://kubernetes.slack.com/messages/wg-app-def)
+* [Mailing list](https://groups.google.com/forum/#!forum/kubernetes-wg-app-def)
+
+<!-- BEGIN CUSTOM CONTENT -->
+
+<!-- END CUSTOM CONTENT -->