Although a robust wage premium for married men has been documented extensively in the labor economics literature, prior studies have been hampered in testing competing explanations of the premium by a lack of data on worker productivity. This study exploits a unique data set that contains job-performance measures for employees of a large, hierarchical organization. The quasi-longitudinal data track the marital status and job productivity, including performance reviews and promotions, of male Naval officers in technical and managerial jobs. Compared with single men, married men receive significantly higher performance ratings and are more likely to be promoted. In estimates that control for selection arising from quit decisions, the size of the marriage productivity effect falls but in most cases remains robust. Also, based on supplementary tests, selectivity arising from the decision to marry appears to explain only a small portion of the unadjusted marriage premium for Navy officers. Although the existence of a wage premium for married men has been documented extensively in the labor economics literature, the source of the premium has remained controversial. One hypothesis attributes the wage differential to economies of scale and specialization within the household, which provides incentives for additional investment in specific human capital by married men (Becker 1981). Alternative hypotheses are that the marriage premium stems from employer favoritism or that more productive or higher earning men are selected into marriage. The extensive empirical literature that has attempted to test the competing explanations has produced conflicting conclusions. However, one research approach to assess the effect of marital status that seldom has been implemented in the prior literature is to use data on the realized productivity of employees of a single firm. This study uses administrative data on male employees of a large, hierarchical organization to explore the effect of marital status on selected job performance measures. The personnel database covers male U.S. Naval officers and contains relatively detailed information on career performance, including promotion outcomes and annual performance reviews. The article seeks to shed light on the existence and magnitude of job-productivity differentials between married and single males and to assess competing explanations for marriage-related performance differentials. Navy personnel data are especially fertile for analyzing the effect of marital status on employee job productivity. Several performance measures are available for each individual, and the indicators capture performance throughout an employee's tenure rather than at a single career point. The design