Among seniors, marijuana use continued its gradual decline, from a 51 percent annual prevalence rate in 1979 to 33 percent in 1988. Between 1986 and 1988, seniors reporting cocaine use declined from 13 percent to 8 percent, following a 6-year period during which use remained fairly level. Also from 1986 to 1988, those who saw great risk associated with occasional cocaine use rose from 54 to 69 percent. For the first time, use of crack cocaine also decreased, concomitant with an increase in perceived risk. In addition to these declines, there were reported declines in the use of nearly all other drugs. Overall, the proportion of seniors using any illicit drugs during the prior year fell 54 percent in 1978 to 39 percent in 1988. The proportion of seniors who could be categorized as current drinkers and or heavy drinkers showed significant declines, and increasing numbers of seniors expressed disapproval of heavy weekend drinking. With regards to cigarette smoking, neither the number of current smokers nor the number of current daily smokers declined significantly from 1984 levels: 29 percent currently smoke and 18 percent smoke daily. 7 tables and 2 figures.