This book has a much wider focus than traditional books written about drug and alcohol addictions. This unique book is written by medical specialists who diagnose, treat and research addictive disorders in their specialities. Thus, it meets the needs of the typical medical practitioner who wants to learn about and treat patients with addictive disorders in their practices. Because alcohol and drug problems are so prevalent and affect medical conditions profoundly, the medical specialist will improve their knowledge and skill to diagnose and treat addictive disorders in their specialties. Drug and alcohol addictions occur commonly in medical populations; 25–50% of patients seen by primary care physicians have alcohol and drug disorders, with even higher prevalence in certain medical specialty populations. Drug use (including illicit drug use and actual or perceived misuse of prescribed medications), alcohol use, and what has been called unhealthy drinking are even more common in trauma centers and our society. Currently, there are no authoritative addiction texts that focus on the identification, intervention and management of either “addictive disorders in medical populations” or “medical complications in addiction populations”. Neurobiological progress in the field of addiction has been amazing and evidence-based treatments have developed at a phenomenal pace, with bench to office applications for tobacco, alcohol and drugs. Pharmacological and psychosocial treatments are described here in detail and in practical terms. The medical and mental complications of addiction are explained comprehensively throughout the text. Clinical considerations are the predominant theme, with the standards of clinical practice grounded in the most current research. The chapters include practical presentations of both clinical and research materials, with instruments for screening and assessment and treatment. It will be useful for all those seeking information to help a patient or family with a tobacco, alcohol or drug problem. We hope this book can give answers and direction to the identification and management of addictions and their medical complications in patient populations.