The fields of applied sport psychology and mental training have grown significantly. Professionals in psychology and the sport sciences are drawn to the opportunities for career advancement and fulfillment our field has made available. The fields of applied sport psychology and mental training have a long history of helping athletes in many sports and around the world. Comprehensive Applied Sport Psychology (CASP) is scientifically rigorous, grounded in the latest applied sport psychology and mental training theory and research. The goal of CASP is to define and explain what applied sport psychology and mental training is and can be in the most broad, deep, and sophisticated way possible and, yet, also to make it useable in consultants’ daily work lives. The various members of a sports community reach out to us to provide a structured program and progression that will lead them toward their goals. The chapter also provides an overview of the key concepts discussed in this book.