Joan McCord (1930-2004) was one of the most famous, most-respected, and best-loved criminologists of her generation. A brilliant pioneer, Dr. McCord was best known for her work on the Cambridge-Somerville Youth Study, the first large-scale, longitudinal experimental study in the field of criminology. The study was among the first to demonstrate unintended harmful effects of a well-meaning prevention program. Dr. McCord's most important essays from this groundbreaking research project are among those included in this volume.McCord also co-wrote, edited, or co-edited twelve volumes and authored or co-authored 127 journal articles and book chapters. She wrote across a broad array of subjects, including delinquency, alcoholism, violence, crime prevention, and criminal theory. This book brings her most important and lasting work together in one place for the first time.