In most epidemiologic studies of occupational stress, work exposure is measured at only one point in time. This article presents a methodology for measuring the intensity and duration of work organization exposure over a lifetime. A job-exposure matrix for work organization was developed from data on a random sample (N = 12,084) of the Swedish labor force. The matrix consisted of mean exposure estimates for work control, social support, psychological and physical job demands, and job hazards for 261 occupations. Several validations of the matrix were undertaken. The matrix scores were found to be significantly correlated with individual self-report scores, and a similar increase in chronic disease prevalence with decreasing work control was found for both the matrix and the individual scores. The matrix was applied to occupational history data to construct lifetime exposure profiles. Potential problems in using attribution systems for exposure assessment are discussed.