There are a few factors here. Besides demographics (mentioned by jobu) there's self-protection: women and minorities are penalized for promoting women and minor

There are a few factors here. Besides demographics (mentioned by jobu) there's self-protection: women and minorities are penalized for promoting women and minorities. So neither a female boss nor a female subordinate really wants to work with the other, because together they can't both win (on average). Just game theory given current constraints. And that's why guys don't mind having a female boss -- there's not the same penalty for either. http://aom.org/News/Press-Releases/Women-and-minority-corporate-executives-are-penalized-for-fostering-diversity,-study-finds.aspx http://aom.org/News/Press-Releases/Women-and-minority-corpor...