The disadvantages experienced by mentally retarded offenders at the hands of the criminal justice system are listed, with emphasis on the lack of appropriate services and the fact that mentally retarded offenders suffer disproportionately from the injustices within the correctional system. The definition, frequency, causes, and classification of mental retardation are explained. Common indicators of mental retardation and formal assessment procedures are described. Psychological considerations in dealing with a mentally retarded offender and practical suggestions for communications are given. A discussion of the special needs of the mentally retarded offender covers the need to develop independence, the difference between habilitation and rehabilitation, and habilitative programing. Legal procedures and their implications are examined, including the protection of legal rights, bail, statements and confessions, criminal responsibility, challenging mental capacity, and sentencing. Recommendations for use by rehabilitation and criminal justice personnel, organizations and their addresses, 62 references, and statutes and cases are listed.