The European labor market is currently facing a critical challenge in harnessing a skilled workforce amidst a backdrop of gender diversity imperatives. This study explores the effectiveness of diversity and equality measures in advancing women in business, utilizing the subjective perceptions of human resources (HR) employees across various sectors within Europe. A comprehensive survey, commissioned by the European Climate, Infrastructure, and Environment Executive Agency (CINEA) in 2023, involved computer-assisted telephone interviews with HR employees from 2500 corporations in the energy industry across Europe. The research employed regression analysis to assess the impact of diversity and equality measures on three dependent variables: the percentage of women among employees, in management positions, and in R&D roles. The results suggest that measures to promote women in companies in the energy industry are only effective to a very limited extent. The basic proportion of women in the companies appears to be more related to the respective industry subsector. Measures to promote women have a greater influence on the proportion of women in management and R&D positions. The respective region of the company also has a significant influence here. Job-sharing in management positions emerges as a singularly significant measure. This research enriches the dialogue on gender diversity within the European labor market, underscoring the necessity for comprehensive strategies for the advancement of women. Furthermore, it spotlights job-sharing in leadership roles as a powerful strategy for bolstering gender diversity. Although the findings are promising, they also highlight the challenges in drawing direct cause-and-effect correlations in the pursuit of gender equality.