Check out this McKinsey Quarterly article entitled A Business Case for Women by Georges Desvaux, Sandrine Devillard-Hoellinger, and Mary C. Meaney [free registration required]:
In recent years, McKinsey has done extensive work on the relationship between organizational and financial performance and on the number of women who are managers at the companies we’ve studied. Our research has shown, first, that the companies around the world with the highest scores on nine important dimensions of organization—from leadership and direction to accountability and motivation—are likely to have higher operating margins than their lower-ranked counterparts do (Exhibit 1).5 Second, among the companies for which information on the gender of senior managers was available,6 those with three or more women on their senior-management teams scored higher on all nine organizational criteria than did companies with no senior-level women (Exhibit 2).7
These findings suggest that companies with higher numbers of women at senior levels are also companies with better organizational and financial performance. Although the analysis does not show a causal link, our research argues for greater gender diversity among corporate leaders.
There's an accompanying piece on how talented women thrive in corporations.
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While on this topic, let me link to this HBS Working Knowledge piece: How Female Stars Succeed in New Jobs:
Women tend to do better after a move for two reasons.
One is that they are more invested in external than in in-house relationships. There are four main reasons why star women maintain external focus: uneasy in-house relationships, poor mentorship, neglect by colleagues, and a vulnerable position in the labor market. External focus makes them more "portable" in terms of making a positive move, but can cause problems if they want to progress within their own organization, because you need a solid internal network and good political capital to get things done in organizations. Anyone who focuses mostly on external relationships will not have that.
The other reason is that women do far more due diligence when they receive a job offer than men do, because women need to ensure that the company is good for women and that they won't be treated as token females. In the process of due diligence, star women learn a lot of valuable information about the company that helps them make good strategic decisions. They scrutinize prospective employers on receptivity to women, managerial support, latitude and flexibility, and performance measurement. There's no downside to that strategy—it is one that men could benefit from just as well.