This chapter reviews the effectiveness of preventive interventions in reducing delinquency and later offending. This focus has three key features: interventions are implemented in the early years of the life-course; before children or young people engage in delinquency in the first place; and they are developmental or social in nature. Early childhood prevention programmes are aimed at the improvement of children’s learning, social and emotional competencies, and success over the life-course. The chapter draws upon the highest quality evaluations (i.e., randomised experiments and sound quasi-experiments) and the most rigorous review methods (i.e., systematic and meta-analytic) that include only high-quality studies. It finds that there are many types of effective preventive interventions, including preschool intellectual enrichment, social skills training, parent management training, parent education, anti-bullying programmes, and community-based mentoring. Explanations for effectiveness vary, and reviews have proven helpful for understanding what theoretical orientations and programmatic features are associated with effectiveness.

This chapter discusses approaches to social prevention, developmental prevention, structure and agency, theory to policy, and the limits of social prevention. It investigates a range of prjects, and asks what progress Australia and other countries have made recently in translating the crime prevention promise apparent in these experiments into effective and sustainable programs. In doing so, it argues that the process has proven difficult, identifying the problem at a political and communicative level. However, difficulties do not just relate to politics and communication. Even among criminologists who agree, in principle, that investment in human capital and infrastructure can have significant prevention benefits, there is little consensus on how such understanding should translate into policy and even whether, at the grassroots level, it is wise to draw too close an association between social intervention and the reduction of crime. These debates have important implications, not just for the ways strategies and programs are designed and implemented but also for the ways they are reviewed and evaluated.