In 1984, suicide rates for 15- to 19-year-olds was 9 deaths per 100,000 population. Very few children under age 12 successfully commit suicide, although many threaten to do so; and some even attempt it. Incidence increases after puberty, peaking at age 23. In the United States about five times as many boys as girls commit suicide, but suicide attempts are more common among girls. In females, suicide is more likely to be associated with depression or transient situations, while in males it is more often associated with a pattern of aggressive behavior, often coupled with substance abuse. In the United States, suicide rates are higher for whites of all ages than for blacks and are highest in the Western States and Alaska and lowest in the South, North Central, and Northeastern States. Firearms are the most frequently used method of suicide for both sexes. Over the past 20 years, suicide has become less common among the middle-aged and elderly and has increased among adolescents. Studies indicate that exposure to media coverage of adolescent suicide, mental illness, obstetric complications, previous suicide attempt, situational crises or stressors, abnormal family history, and certain neurochemical factors are associated with increased risk of suicide. Available research suggests that such risk factors can provide a basis for preventive and treatment efforts focused on high-risk subgroups. 2 tables and 48 references.