In her qualitative case study, Jeannette Trenkmann addresses the question of why equality policy measures in companies of the German private sector remain ineffective. To answer this highly relevant issue from both practical and theoretical perspectives, the author identifies who contributes to the institutionalization of corporate equality policies—and thus to increasing the number of women in leadership positions—how they do so, and why. She emphasizes the roles of organizational actors and their institutional work. The findings contribute to the successful and sustainable realization of equal opportunities and gender equity in companies.