Clients enter therapy grappling with a range of difficulties. They don’t speak in diagnostic terms, but instead focus on the everyday problems that confront them. Their struggles may include isolation, loneliness, anxiety, guilt and regret, and problems making decisions in a world that offers seemingly endless choice. In contrast, the cognitive-behavior therapist is trained in the language of conditioning and extinction, avoidance and safety behaviors, behavioral activation and attentional biases. This book explores the ideas of the existentialist philosophers as a bridge between the suffering client and technically trained clinician. The volume is not a rejection of cognitive behavior therapy (CBT), but seeks to place CBT in the broader context of the most popular philosophic tradition of the 19th and 20th centuries.  Therapists versed in existentialism argue that the individuals starting point is characterized by a sense of disorientation in the face of an apparently meaningless and absurd world. Each individual must become solely responsible for giving meaning to life and living it passionately and authentically. Each of us must confront the ‘Big 5’ existential issues of death, isolation, identity, freedom and meaning and find our solutions to these problems.  The present volume explores each of these existential themes in turn. Each section opens with a theoretical chapter describing the relevant existential dilemma and its impact on human experience. The second chapter in each section explores its relationship to mental health disorders and psychopathology. The third chapter in each section explores the evidence for treating the existential issue from a CBT framework. This book will be of value to those interested in CBT, philosophy and mental health, and will appeal to psychotherapists, clinical psychologists and psychiatrists.