A review of major implications of the O'Connor v. Donaldson decision.

Although the Supreme Court's decision in O'Connor v. Donaldson is narrow from the legal perspective, it will have wide clinical applications for psychiatry if it reflects a trend in future court decisions. The author assesses the impact of this decision on the mental health profession in terms of the issue of dangerousness as grounds for involuntary commitment for psychiatric treatment, the principle of least restrictive alternative to hospitalization, the question of adequacy of treatment in light of the absence of nationally defined standards, and the personal liability of physicians for their professional actions.