In recently published articles, there has been an underemphasis on the role serious mental illness (SMI) plays in causing persons to be in the criminal justice system. Increasing attention has been paid to other factors, including criminogenic needs. While these needs may be present and contribute to criminal behavior, persons with SMI who are at greatest risk of criminalization are those who are not receiving adequate treatment, structure, social control, and, when necessary, 24-hour care in the mental health system. Cognitive behavioral therapy (CBT) has been used to reduce recidivism for prisoners, including those with SMI, but persons impaired by their untreated psychotic symptoms may not be able to profit from it. The importance of psychiatric treatment must not be underestimated. Moreover, given their current constraints, correctional systems may not be able to continue accepting large numbers of persons with SMI. Many offenders with serious mental illness pose difficult and expensive problems in treatment and management, such as nonadherence to medication, potential for violence, and substance abuse. The mental health system needs to be given more funding and to take more responsibility for these challenging individuals.