Today's brainteaser: Name the top female executives who were forced to go before Congress, explaining why their companies made multibillion-dollar mistakes that helped wreck the economy but nonetheless deserve billions in taxpayer bailouts.

    Stumped?

    If you can't come up with any, it's probably not because you haven't been captivated - and enraged - by the drama of corporate chieftains shifting uncomfortably in congressional hearing rooms. You're getting a bird's-eye view of what Catalyst, the business-backed research group that's been tracking women's advancement in the corporate world since the 1960s, saw when it took its annual look into the nation's executive suites: Women just aren't there in numbers sufficient to make them visible.

    After more than three decades of pushing and prodding, of dressing - for success and avoiding the trap of the "mommy track" - and despite the elimination of laws and practices that previously put women out by the water cooler rather than in the corner office - American businesswomen still are not climbing to the top.

    In the last few years, in fact, even the glacial progress that was being made has slowed. Fewer than 16 percent of senior corporate officers at Fortune 500 companies are women, the group found, roughly the same proportion that filled these key decision-making jobs since 2002. The number of women who sit on corporate boards - the panels that are supposed to demand answers when balance sheets, business forecasts or, say, executive pay packages just don't look quite right - is stagnating as well. Women held a 15.1 percent share of board director positions in Fortune 500 companies in 2008, barely changed since 2005. The number of corporate boards with no women, or only one, two or three, also is essentially unchanged.

    Should We Sigh? Or Scream?

    For years we were assured that once there were enough well-credentialed women in the "pipeline" that leads to professional advancement, they would be rewarded - just as men with college diplomas and advanced degrees always have been. Now women outpace men in many areas of educational attainment. They comprise about half the nation's law students and receive more than a third of MBAs. But something seems to happen between the time they are handed their diplomas and the day big promotions are handed out.

    "It used to be thought that it was just a matter of time, that the more women we produced, the more women would move up," says Ilene H. Lang, president and CEO of Catalyst. "That might be true in the colleges, that might be true in middle managers." But at the very top of the corporate hierarchy, barriers to women's advancement that are rooted in stereotyping still block their paths. Lang said research shows that assumptions among both women and men are that women aren't ambitious enough, or don't really care about money as much as men do. But, Lang says, "Our research shows that women and men want the same things out of work. They want challenging work assignments and a supportive work environment. Men are more able to get the challenging work assignments and the supportive work environment."

    And what about those much-discussed "life choices" that women supposedly make, which tether them too tightly to home and hearth when what's needed is undivided loyalty to the corporate team?

    The values that senior executive men and women have for balancing work and life turn out to be not very different. In an earlier survey by Catalyst and research partners, conducted among senior men and women at corporations with global operations, men ranked the value of "having a good fit between life on and off the job" fourth out of six job attributes; women ranked it third.

    So long as the invisible barriers to women's advancement remain, business will be drawing its leaders from only half the available talent pool. Could this myopia have helped plunge us into the current economic swamp? The possibility is not easily dismissed. Though there certainly are women who've become symbols of corporate villainy - the late hotel mogul Leona Helmsley comes to mind - few women executives have been associated with the greed-is-good crowd.

    Now that so much has been destroyed and so much is to be rebuilt, there's an opportunity to bring new voices and perspectives into the conference rooms. This is a fine time for new management that is genuinely new.