This paper analyses the determining factors of PhDs' career success. Earnings have been used as an objective measure, and a subjective measure of success was constructed based on the individuals' assessments of broader aspects of their job position. When analysing the data by field of knowledge and gender, it was found that males and PhD holders in the field of sciences achieve greater career success in terms of earnings. However, the theory of the glass ceiling does not appear to apply. On the basis of a subjective measure of career success, on the other hand, it is women and PhD holders in humanities and social sciences that are more successful. Regardless of the measure of success used, the most important determining factor in career success is job satisfaction, thus reinforcing the theory that PhD holders are a group of workers with a more complex conception of career success.