MDSO laws are intended to target the sex offender for institutionalization and treatment. The paucity of effective treatment methods for sex offenders and the absence of treatment altogether have made MDSO laws vulnerable to legal challenge and have prompted prosecutors to seek the conviction and sentencing of sex offenders under relevant criminal law rather than MDSO laws. The interest in developing effective treatment techniques for sex offenders persists, however, with the focus on matching offenders to such treatment methods as psychotherapy, behavior modification, and the use of psychopharmacologic agents. Legal rights which must be addressed in treating sex offenders are the ability to give informed consent to treatment, the voluntariness of consent, the right to treatment, and the right to refuse treatment. Legal issues pertaining to the treatment provider are informed consent, confidentiality and the duty to warn persons who may be harmed by the patient, compliance with child abuse reporting statutes, and malpractice liability. 65 footnotes.