The first part of the book consists of eight chapters designed to help readers understand adolescent substance use. A chapter on terminology and classification focuses on the evolution of the nosology of psychoactive substance use disorder, followed by a chapter on the epidemiology of ASU and APSUD. The latter chapter considers trends in the use of specific drugs per subpopulations and summarizes drug-use trends according to grade, sex, and ethnic/racial variables; trends in attitudes and beliefs about drugs among high school seniors are also discussed. Other chapters in this first part of the book address the etiology and pathogenesis of ASU and APSUD, APSUD and psychiatric comorbidity, the relation of ASU and APSUD to suicidal behavior, HIV and AIDS and APSUD, and maternal and infancy addiction. Three chapters in Part II focus on the prevention of ASU and the assessment and treatment of APSUD. Chapter references and a subject index