The first edition of this book has come to fruition out of the professional observations and experiences of the authors and those that they have supervised and trained. While counsellor preparation programs frequently require a course in counseling assessment, school counselors-intraining often report dissatisfaction in the relevance of what is covered, as the content is not focused on what school counselors actually see and use in practice. Prior to this book, no resource existed that focuses on the concept of assessment specifically for school counselors and provides them with formal and informal assessments that provide opportunities for data collection that, in turn, informs one’s data-driven, comprehensive school counseling programs (CSCP). Whether it be individual student data, school level data, school counseling program level data, or about the school counselors’ practices or beliefs, this professional resource offers a unique opportunity to meet the call from school counseling professionals to have guidance and access to instruments that focus on multiple levels of data. The book bridges the gap in knowledge and skills to allow school counselors to carry out their critical work in advocating for student success every day, based upon data. From this resource, the authors hope readers will gain the necessary attitudes, knowledge, and skills that are required to be a data-inspired and data-driven school counselor who serves as a leader and agent of change as a part of the development and implementation of a comprehensive school counseling program. One of the most salient and unique features of this book is that it offers readers with actual assessments that could be immediately implemented in one's school. The intended audience for this book is school counselors-in-training, practicing school counselors, those who serve in a district-level supervisory or coordinator position, as well as school counselor educators.