We examined the interplay between three explanatory hypotheses for why older adults appear to rate their problems as less stressful than do younger adults: age-related differences in personality, in types of problems, and in the appraisal process--specifically, the number of primary stress appraisals. A sample of 1,054 men from the Normative Aging Study (mean age = 65.02; range = 45 to 92) were interviewed about a problem in the past week. Personality did not mediate the effect of age on stress ratings. While general hassles and health problems both increased with age, they had opposite influences on stress ratings. Accounting for covariates, older men reported fewer appraisals, and the number of appraisals mediated the association between age and stress ratings. We found no moderating effects of problem type on these processes. Thus, lower stress ratings for everyday problems in later life may result from developmental changes in primary appraisal processes. (Contains 2 tables and 2 figures.)