Advances in sleep medicine research are  improving our clinical work for individuals with sleep problems. The aim of this book is to educate psychiatrists and other mental health professionals about the importance of understanding sleep disorders, including their bidirectional relationship with psychiatric conditions. This book consists of six major sections with seventeen chapters. It is led off by an introduction on the function of sleep, its neurophysiology, and types of sleep problems. Since insomnia represents a common and significant challenge for patients with psychiatric disorders, its clinical presentation and treatments are reviewed in the second section. Cognitive behavioral therapy for insomnia (CBT-I), mindfulness-based CBT, acceptance and commitment therapy (ACT), and the medication management of insomnia are reviewed. A third section addresses sleep related breathing disorders. The pathology of sleep apnea, its treatments, and therapeutic modalities to address non-compliance with positive pressure ventilation are reviewed. Other sleep disorders such as hypersomnia, circadian rhythm disorders, movement disorders and parasomnias are discussed in the fourth section. Since features of sleep disorders can vary by age, gender, and trauma history, a fifth section discusses the unique sleep problems associated with children, women, older adults, and veterans. The book concludes with a final section discussing how sleep disorders and psychiatric conditions overlap. We hope this book highlights the importance of understanding and addressing comorbid sleep disorders among individuals with psychiatric conditions. We are confident that this book will be valuable in helping clinicians improve the management of sleep disorders in their clinical practice.