The data indicate that for the period between July 1988 and July 1992, the number of adult/adolescent AIDS cases increased more than 3.5-fold from 67,141 to 226,281. The proportion of cases diagnosed among homosexual/bisexual males declined 5 percent, but the proportion of persons with AIDS who reported a history of intravenous drug use increased by 3 percent. The proportion of cases that are attributable to heterosexual contact increased from 4 percent in 1988 to 6 percent in 1992. Blacks and Hispanics accounted for 40 percent of the cases in 1988 and 45.5 percent by 1992. If this trend continues, these two minority groups will account for half of the diagnosed AIDS cases within the next five years. There was a small increase in the cumulative proportion of female cases between 1988 and 1992, but males still account for almost 90 percent of the total cases to date. Homosexual/bisexual activity is the sole risk factor in approximately two-thirds of the diagnosed cases of males. One-half of the females diagnosed with AIDS report a history of intravenous drug use as compared with 35 percent who become infected through heterosexual transmission. The data indicate there has been no marked change with regard to the epidemiology of the AIDS epidemic. 8 tables and 15 references