The latest release of Windows Azure Toolkit for Windows Phone 7 integrates with the Windows Azure AppFabric Access Control Service! In this screencast you will learn: How to use the project templates to create a Windows Phone application and backend secured via ACS How to find your way around the resulting application If you want more details about the ACS integration, check out this post from Vittorio's blog. For more information about the toolkit please refer to Wade Wegner's post here, the documentation and the Getting Started video here.