This introduction offers a primer for this special edition of the Journal of Contemporary Criminal Justice. The purpose is to provide an interdisciplinary platform for scholars and practitioners to communicate perspectives of criminal justice, criminology, and law; public policy and administration, economics and political science; social work and sociology; behavioral health, counseling and psychology; public health, emergency medicine, and psychiatry around diversion. While disciplines share objectives of diversion as (1) rehabilitation, (2) efficient case processing, and (3) reducing resources, the defining and reporting of diversion differs. Justice-involved individuals with mental health issues making successful re-entry into the civil society, however, becomes convoluted. Diversion in practice has taken many shapes. Diversion in theory has taken many meanings. This special edition offers a variety of empirical and theoretical articles that attempt to provide clarity to an often implemented and understudied area of criminal justice and health care. Interviews with street-level officials, quantitative analyses of programs, and philosophical challenges to innate assumptions about individuals and systems are seen from a wide variety of scholars. The authors showcase their varied backgrounds with graduate students, university faculty, and practitioners, offering the fields of criminal justice and health care insight into diversion at all levels.