Women tend to earn fewer promotions (Roth et al., 2012) and receive fewer developmental opportunities (King et al., 2012) than men, but little research explains why. I explore the stereotype of the ideal worker, someone who meets their supervisor's expectations and has the potential to be promoted to the top levels of their organization over their career, as one reason for this disparity. I propose that supervisors use this stereotype to assess employee promotability and developmental opportunities. I explore the attributes of the ideal worker stereotype using the theory of gendered organizations (Acker, 1990, 1992), which suggests that firms operate from a masculine perspective because men tend to create and lead organizations. I find that the attributes of the ideal worker are broader than suggested by the theory of gendered organizations and past research on the ideal worker, but that these attributes are not perceived as masculine. In addition, I find no differences between how men and women are rated in terms of promotability, recommended development, and the extent to which they exemplify the attributes of the ideal worker. However, the extent to which employees exemplify ideal worker attributes predicts promotability ratings and development recommended for them. Sexism, an individual difference among raters, moderates the relationship between employee gender and outcomes such that women receive lower ideal worker ratings and less recommended development when raters have high sexism beliefs. I also find that the implicit (unconscious) associations between ideal worker attributes and gender role stereotypes affects recommended development such that those with masculine implicit associations give more development to female employees. My dissertation presents future research opportunities to further investigate the ideal worker stereotype and its impact in the workplace.