This session provides an introduction to developing custom data connectors for Power BI using the Power Query SDK and the M programming language. The session begins with a quick primer on M programming syntax and then explains the motivation and key scenarios for creating custom data connectors. Attendees will learn how to get started developing custom data connector projects using Visual Studio 2017 and the Power Query SDK. The session will demonstrate how to author shared query logic in a custom data connector that can be reused across multiple projects created with Power BI Desktop. Attendees will learn how to package a custom data connector as well as how to test it locally using Power BI Desktop. This session concludes by explaining how to design and implement custom data connectors that authenticate with Azure AD and acquire access tokens making it possible to create queries that call into the Microsoft Graph API.