Book excerpt: Youth and Their Families explores adolescent substance abuse in the context of Family Systems Therapy (FST), which helps clinicians view their client as an entire family system being affected by the issue. FST can be used at every stage of the substance abuse intervention continuum--from prevention to intervention--to provide increased functioning and strength in the family system. This book incorporates easily applicable clinical skill acquisition with the use of lively cases to give the reader requisite skills to be an effective family systems therapist.