The higher the hierarchical level, the fewer women are represented in management positions. Many studies have focused on the influence of human capital and other "objective" factors on career opportunities to explain this phenomenon. We are now looking at the impact of self-reported personality traits on gender differences in career chances and compare women and men in management positions and other white-collar employees in Germany's private sector 2007. While bivariate results based on data from the German Socio-Economic Panel (SOEP) show that there are significant gender differences in personality traits, multivariate estimations and the decomposition of the gender career gap clearly indicate that these differences cannot account for gender differences in career opportunities. The decomposition shows that only 8.6 percent of the inequality of career chances between women and can be explained by differences in personality. Nevertheless, personality traits might indeed play a role, albeit more indirectly: Some of the stronger career effects, such as long working hours, and labour market segregation, can also reflect differences in personality traits. These might have been influenced at an early stage by a gender-biased environment. Our results strongly stress the need for a gender-neutral environment outside and inside companies in order to enforce equal career opportunities for women and men.