We study how organizational sex composition influences the intraorganizational mobility of male and female managers. We test hypotheses linking organizational sex composition to hiring and promotion using longitudinal data on all managers in the California savings and loan industry. We find that the impact of sex composition depends on hierarchical level: Not only does it matter what relative proportions of men and women are working in organizations, but it also matters at what levels in the managerial hierarchies they are working. Our findings demonstrate a catch-22 situation: Women are more likely to be hired and promoted into a particular job level when a higher proportion of women are already there. The question remains, how can women gain entry into these positions? We also find that women are more likely to be hired and promoted when there is a substantial minority of women above the focal job level, but not when women constitute the majority in those higher-level positions: Hence women in high ranks can sometimes be a force for demographic change. Finally, we find evidence that women are more likely to be hired and promoted when higher proportions of women hold positions below the focal job level, indicating that gains made by women are not entirely dissipated by endogenous organizational processes.