The primary purpose of this paper is to improve on the specification of job experience as measured by current age, minus age at completion of formal schooling. The process of acquiring productive job skills was modeled by first focusing on the determination of the level of first-job occupation and then, given initial occupation, examining the determinants of occupational advancement. The impact of initial occupational level and occupational change on current (1966) wage rates were then examined. In the empirical analysis, separate equations for middle-aged black and white men were estimated to focus on racial differences in the acquisition of labor market experience. The primary finding is that it is work experience accompanied by occupational advancement, rather than work experience per se, that has an effect on the distribution of wage rates. (Author/HD)