Legitimate concerns on the part of parents and guardians may lead to requests for sterilization of a mentally retarded person in their care. At the same time, mentally retarded persons must be protected from actions that do not serve their best interests. This paper will review the history of involuntary sterilization in the United States and evaluate the ethical arguments that are relevant to decisions about involuntary sterilization. While other, less permanent forms of contraception might be acceptable, involuntary sterilization ought not be performed on mentally retarded persons who retain the capacity for reproductive decision-making, the ability to raise a child, or the capacity to provide valid consent to marriage. Mentally retarded persons who lack capacity in those three areas should be considered for involuntary sterilization only when the procedure is necessary, sterilization would serve the best interests of the mentally retarded person, less intrusive and temporary methods of contraception or control of menstruation are not acceptable alternatives, and procedural safeguards have been implemented to assure a fair decision-making process.