A review of problem gambling in forensic populations suggests that one third of criminal offenders meet criteria for problem or pathological gambling. This is the highest rate yet found in any population. Approximately 50% of crime by incarcerated problem and pathological gamblers is reportedly committed to support gambling. The prevalence of gambling within correctional facilities (40%) appears lower than in the general population. However, inmates who do gamble tend to do so regularly, and problem and pathological gamblers are disproportionately represented among this group. Inmate screening for problem gambling and provision of specialized treatment are currently lacking in most correctional facilities. In addition to more screening and treatment, there needs to be greater vigilance in detecting gambling and enforcing its prohibition.