Elderly offenders have rarely been studied. We describe a population of elderly offenders referred to a forensic psychiatric service over a 20-year period (1972-1992). Patients over 65 years charged with a criminal offence were eligible for inclusion. For the purpose of the study they were divided into four study groups. Demographic data, forensic and psychiatric history, alcohol abuse, charge and psychiatric diagnosis are reported. The possible reasons for the high proportion of sex offences are discussed. Difficulties were encountered in the transfer of longstay elderly offenders back to their local area. Finally, we recommend that most of the elderly patients referred to the forensic service for treatment would best be cared for in their local catchment area hospital rather than in a high security hospital.