The empirical analysis examines differences in salaries and working time of doctorate holders in comparison to graduates with a master or equivalent degree (in Germany, the first university degree is called a "diploma" or "state examination" depending on the field of study. The diploma degree and the state examination are equivalent to a Master's degree as they typically require a 5 year full time study program. Only recently, after the implementation of the so-called Bologna reform in 1998, have German universities started to introduce Bachelor and Master's degrees), distinguishing between different fields of study. Human capital theory is used as the theoretical basis for our empirical analysis of a sample from the microcensus (2006) of the German Federal Statistical Office. The results indicate that doctorate holders tend to work longer hours than graduates with a master degree, especially doctorate holders in Economics and Law and the Social Sciences. Moreover, a doctoral degree has a positive effect on the income-situation in nearly all tested fields of study. Graduates from the field of Economics and Law in particular earn comparatively high incomes.