Drinking behavior was studied in a random sample of 1043 adults in the Boston [Massachusetts, USA] metropolitan area. Respondents were grouped into 5 categories, from abstainers to heavy drinkers, according to the Index of Quantity-Frequency-Variability. More men than women in all age groups were heavy drinkers: 54 vs. 21% at age 18-24 and decreasing proportionately to 19 vs. 3% at age 65+. The percentages of men and women who were abstainers increased from 3 and 14% at age 18-24 to 22 and 37% at age 65+. There were no significant differences between Black and White men. A higher proportion of Black than White women were abstainers (36 vs. 17%), but similar proportions were heavy drinkers (11 vs. 12%). Of the separated and single men 1/2 were heavy drinkers vs. 0.33 of the married and 13% of the widowed. Among the divorced and separated women, 24% were heavy drinkers vs. 12% in other marital status categories. There were no significant differences in drinking patterns by ethnicity when controlled for sex. When correlating sex and social class, 62% of lower social class women, 36% of middle and 25% of the upper class were abstainers and infrequent drinkers. Among men, 34% of the lower social class, 20% of middle and 16% of the upper class were abstainers and infrequent drinkers.