This edited volume describes key domains of the emerging research literature linking exercise and mental health. The volume is divided into three sections. The first section provides an overview of foundational knowledge regarding basic processes of exercise, including neurocircuitry, neurotransmitter, and immunology systems. The second section describes emerging research on the acute impact of exercise on affect, mood, and cognition. The third section explores the role of exercise in the etiology and treatment of related mental and physical health disorders, including depression, PTSD, eating disorders, and autoimmune disorders. Collectively, this volume provides readers with foundational knowledge of what exercise is, the basic brain, behavioral and cognitive processes engaged by exercise, and a role of exercise in developing and treating mental health disorders.