This paper contributes to our understanding of the causes of the restriction of women from positions of authority in the workplace. We ascertain the extent to which the sex gap in aspects of authority can be explained by the following three factors: (1) women's qualifications, (2) the behaviors and policies of employers, and (3) the attitudes and behaviors of women themselves. We find that while the amount of sex difference in aspects of authority that can be explained by women's qualifications is substantial, it is not the most important factor responsible for the restriction of women from positions of authority. Furthermore, strong evidence is presented that suggests that the behaviors and policies of employers are much more important causes of sexual differences in authority in the workplace than are the attitudes and behaviors of the women themselves.