To examine risk factors for disease-specific survival in young and older adults diagnosed with Hodgkin's disease (HD) in a representative case series of adequate size for detecting effect modification by age group. For 5630 young adults (ages 15-44) and 2424 older adults (ages 45 and older) diagnosed with HD and reported to the population-based Surveillance, Epidemiology, and End Results program of the National Cancer Institute between 1983 and 1995, Kaplan-Meier survival curves were constructed and Cox proportional hazards regression used to evaluate the influences of age, sex, race/ethnicity, histologic subtype, Ann Arbor stage at diagnosis, and calendar year on hazard of disease-specific death. The effects of most previously studied risk factors for HD death were different for young and older adults. Age was not associated with disease-specific survival in young adults, but in older adults, 1-year increases in age elevated the relative hazard of HD death by 4 6%. Male sex was related to outcome in young but not older adults, and Ann Arbor stage and B-symptom status exhibited markedly different relationships to survival by age. Older adult patients with and without B-symptoms had different hazards of mortality and had to be assessed separately. Factors associated with disease-specific survival were different for young and older adults with HD. These findings provide further support for two etiologically and clinically distinct disease entities.