Monozygotic twins reared apart from an early age were used to test the hypothesis that there is a significant genetic component to job satisfaction. Thirty-four monozygotic twin pairs who had been reared apart completed the Minnesota Job Satisfaction Questionnaire as part of a comprehensive work-history assessment. Three subscales were formed from the job satisfaction items to reflect intrinsic, extrinsic, and general satisfaction with the current (or major) job. Intraclass correlations were computed to estimate the proportion of observed variability resulting from genetic factors for all job satisfaction items and for the three subscales. Resulting values indicated that approximately 30% of the observed variance in general job satisfaction was due to genetic factors. Additional analysis indicated that these results obtained even when job characteristics such as complexity, motor skill requirements, and the physical demands were held constant via partialing methods. Finally, the data indicated significant heritabilities for several of these job characteristics, which is consistent with the hypothesis of a genetic disposition to seek and remain in similar environments (jobs). Implications of these findings for theories of job satisfaction, selection, and job enrichment are discussed.