Book excerpt: A great deal has been learned about serious child and adolescent conduct problems, but their causes are still not well understood. This book brings together an international group of leading authorities to advance specific, testable hypotheses about the causes of conduct disorder and juvenile delinquency. Four general causal models are delineated: the social learning model, the developmental pathways model, an integrative antisocial propensity model, and an integrative ecological/developmental model. Also provided are models focusing on specific aspects of the origins of conduct problems, including contextual, psychological, and biological influences. The authors present significant, original theoretical work and map out the kinds of further studies needed to confirm or disconfirm their new or revised hypotheses.