To determine the predictors of mortality and find the life expectancies of adults with cerebral palsy (CP), data on 24,768 individuals aged 15 years and over who received services in California between January 1980 and December 1995 were analyzed. Multivariate statistical methods to identify mortality predictors, and actuarial methods to determine corresponding life expectancies were used. The key predictors were lack of basic functional skills: mobility and feeding. Adults lacking these skills had much reduced life expectancies, as short as 11 years for the worst functioning groups. By contrast, survival of high-functioning adults was close to that of the general population. The influence on survival of cognitive skills, type of CP, and other factors appears to be expressed largely through their effect on basic functioning. Life expectancies of adults of a given age can differ by 40 years or more, according to their functional level.