The author suggests that the frequency and severity of tardive dyskinesia in patients treated with neuroleptic drugs requires that informed consent be obtained from all patients receiving such treatment. The three basic conditions for obtaining informed consent are reviewed with discussion of some of the ethical problems encountered in the informed consent procedure. Most of these problems will be resolved if specific, written, informed consent is obtained from the patient, or his representative, within six weeks of initiating therapy, although in some cases questions may be raised about the very possibility of obtaining consent.