The review of research on police crackdowns (increased officer presence, sanctions, and threats of apprehension) advises that five studies with post-crackdown data showed continued deterrence well after the crackdowns ended. The findings suggests that crackdowns might be more effective if they are limited in duration and rotated across various targets. A review of the use of fines and day fines in American courts found that day fines have proven effective in helping courts set fine amounts that are both proportionate to the severity of the offense and the offender's ability to pay. Some American courts are now adapting day fines to the American context and are beginning to experiment with their use. The essay on the neuropsychology of juvenile delinquency shows that the performance of delinquent juveniles on neuropsychological tests suggests a role for brain dysfunction in the causation of antisocial behavior. An analysis of strategies for addressing the destructive behaviors of youth gangs suggests an integration of the approaches of community mobilization, social support, social opportunities, and suppression coordinated within a framework of social control and institution building. A review of research on crime placement, displacement, and deflection concludes that displacement alone is an inadequate concept; a better formulation centers on the deflection of crime from a target. The essay on parole in transition is a comparative study of origins, developments, and prospects for the 1990's in the United States, Canada, and England and Wales. The concluding essay advises that an examination of developmental processes as juveniles grow older, such as increases in physical strength and motor skills, the emergence of personality traits, sexual maturation, and greater opportunities for crime commission, provides important contextual information for studies of offending. References and data accompany the essays.