This chapter introduces Time-Limited Adolescent Psychodynamic Psychotherapy (TAPP) as once-weekly psychotherapy consisting of 4 assessment and 16 treatment sessions followed by a post-treatment review. It provides an overview of the origins and development of TAPP and highlights that the aim of TAPP is to identify and work with a developmental focus with young people between the ages of approximately 14 and 25, thus engaging with young people in the extended transition to adulthood. The importance of TAPP is discussed in relation to the emergence of time-limited approaches to adolescent psychotherapy and the current context of international concerns about adolescent mental health. TAPP addresses the contemporary experiences of young people and the radical and far-reaching internal changes in the adolescent developmental process. The chapter discusses the scope of the book, providing an overview of its aims and introductions to the following chapters. Part I provides a conceptual framework, consisting of discussions of time-limited psychotherapy, adolescence, adolescent psychotherapy and the emergence of new ways of thinking about therapeutic process and change. Part II discusses the practice of TAPP.