Substance abuse comprises a global biopsychosocial phenomenon for the world as billions of human beings are experimenting with various illicit chemicals and millions are addicted to various substances. By virtue of their complex nature these disorders can be very difficult to treat and not only complicates the natural course of disease but can also adversely impact long term outcomes. This book is aiming to examine this complex situation in adolescents and young adults and also to provide management plans for clinicians to follow.The information will be presented in an easy to follow format to be used as a clinical reference by physicians and paramedical staff in various fields of medicine including pediatrics, primary care, internal medicine, psychiatry and others.