Increased crime by the elderly is noted, and the violent behavior of the aged in medical care settings is traced to their frequent illnesses. Suicide rates are shown to increase with age, rising from 22 per 100,000 in white males aged 22 to 24 to 52 per l00,000 in patients 80 and older. Suicide is more common among lower class than middle or upper class males and is also more common in urban than in rural settings. The elderly suicidal patient is usually depressed, but may be diagnosed as having schizophrenia, epilepsy, or no condition at all. Hospital staff should be able to assess suicidal patients and to protect them from themselves. Other types of violent patients are described: demented, depressed, paranoid, and alcohol or drug abusive. An examination of management of the violent elderly notes that the most important principle is to develop a staff understanding of the origins of the patient's aggressiveness. The use of case-oriented discussions has been found to be particularly valuable. Additionally, in acute care settings, staff should be aware of the elderly's alcohol and drug problems so they will be more likely to recognize withdrawal status and substance abuse confusional syndromes. Regular crisis drills may also be helpful. Twenty-six references are included.