Class action litigation has been instrumental in jail and prison reform during the past two decades. Correctional mental health systems have significantly benefited from such litigation. Forensic psychiatrists have been crucial in the litigation process and the subsequent evolution of correctional mental health care systems. This article summarizes information concerning basic demographics of correctional populations and costs of correctional health care and provides a brief history of such litigation. The role of psychiatric experts, with particular reference to standards of care, is described. Specifically discussed are issues relevant to suicide prevention, the prevalence of mentally ill inmates in supermax prisons, and discharge planning.