Life expectancy for adults with Down syndrome was calculated from data for 1610 liveborn affected individuals identified in over 1,500,000 consecutive live births in British Columbia from 1908 to 1981. Survival to 68 years of age, predicted from the available data, is better than in previous estimates, but is still much poorer than for the general population: about 44.4% and 13.6% of liveborn Down syndrome individuals will survive to 60 and 68 years, respectively, compared with 86.4% and 78.4% of the general population.