The purpose of this guide is to provide information on how to use early warning data, including the Massachusetts Early Warning Indicator System (EWIS), to identify, diagnose, support and monitor students in grades 1-12. It offers educators an overview of EWIS and how to effectively use these data in conjunction with local data by following a six-step implementation cycle. Because no two districts, schools, or students are alike, the guide was purposely developed this as a flexible tool to help educators customize their use of EWIS to fit their individual needs, interests, and resources. It is the hope that this guide will help educators with the important work that they do every day in their classrooms, schools, and districts. The following are appended: (1) The Development of the Massachusetts EWIS Model; (2) Accessing EWIS Data and Reports in Edwin; (3) Sample Early Warning Implementation Timeline; and (4) Targeted and Schoolwide Intervention Resources.