There has been an exponential growth of court-based justice diversion initiatives – such as mental health courts and liaison and diversion services – around the globe since their inception in the early 1990s. In parallel, there has been a growing body of research to describe and assess the effectiveness of such initiatives. This article aims to provide an overview of court-based diversion programmes, identify their effects, and guide future implementation and research. Court-based diversion initiatives are generally effective in decreasing the risk of recidivism, increasing access to mental health services, and decreasing substance abuse. However, their characteristics vary widely in terms of admission criteria, team composition, conditions, incentives, and use of sanctions. Nevertheless, certain factors may influence participation and success of court diversion programmes. These include relations with case managers and use of therapeutic jurisprudence principles. While participants generally experience these programmes positively, legal scholars have raised issues such as upholding procedural rights of participants, and equality within the justice system. Court-based diversion should be analysed within a larger systemic framework so as to better assess its impact in relation to existing mental health and psychosocial services as well as other diversion initiatives along the criminal justice pathway.