One issue involves the use of psychiatric commitment as a means to quarantine those who endanger others by sexual promiscuity or needle-sharing. Laws permitting such commitments are difficult to invoke, the legitimacy of such a use of commitment laws is questionable, and facilities may not be equipped to meet the medical needs of such patients or prevent other patients from being infected. Once HIV-infected patients are admitted, new issues arise relating to the needs to protect the health of staff and patients and the HIV patient's right to confidentiality of all medical information. Controlling dangerous behaviors such as biting may require limitations on the seropositive patient's freedom of movement. Control of sexual behavior of such patients also may be problematic and may entail the disclosure of HIV status to third parties in need of protection. This situation is further complicated by a possible duty to warn identified and even unidentified sexual partners of the HIV-infected patient and by some State laws prohibiting disclosure of a patient's HIV status without consent. Such legal problems already have been experienced in mental health facilities and are likely to increase in the future. 14 references.