And what are the traits that define Book's new brand of female leadership? A high threshold for risk, a collaborative style, and a willingness to reinvent the rules -- in other words, the same traits of any successful executive, male or female. While Book trots out some research from the late 1980s and early 1990s in an effort to make the case that women have an innately different (read: better) leadership style than men have, she fails to explain why, if this is so, women still haven't made much progress.

In fact, what Book and Evans both ignore, and what Orenstein focuses on, is the most obvious difference between women and men: Women bear children and are more involved in raising them than men are. It is probably no coincidence that Evans began her career at CNN once her children were older and in school. And many of the superstars that Book writes about never had children (a fact that she conveniently glosses over) . In one survey of senior executives that is cited by Orenstein, more than half of the women have never been married, divorced, or widowed -- and fewer than 40% of them are mothers. In contrast, 95% of the men in the survey are married with children, and 75% have stay-at-home wives.

This contrast makes up the heart of Flux.Why is it, Orenstein asks, that women still find that having a career and having a family are at such odds? Interviewing high performers in various circumstances -- from a 26-year-old junior executive who vows never to have kids to a 38-year-old prosecutor who quits a job that she loves in order to care for her kids -- Orenstein argues that women's work-family conflicts have as much to do with their own perceptions of motherhood as with the attitudes of corporate America.

Women in their 20s -- what Orenstein calls the "Promise Years" -- start thinking about how they're going to negotiate work-family issues long before they are even married. While they wish for equality in relationships and in the workplace, they see few role models who "have it all" and conclude that their wish is unattainable. As a result, some women give up the idea of having a family, while others cling to a traditional definition of motherhood -- in which women are the primary caregivers -- and make career and mate choices accordingly.

One young doctor profiled by Orenstein chooses radiology as her specialty because it has the kind of regular hours that will make it easier to be a mother and a wife -- even though she doesn't have a boyfriend, let alone a family. Another woman dumps her "wonderful" boyfriend because of his limited earning potential. While these women see themselves as being pragmatic, Orenstein argues that they're just ensuring that they'll earn less than their mates and so will have less leverage down the road when it comes to negotiating who will handle household chores or child-care duties.

By the time women near their 40s, many of them are in the grip of what Orenstein calls "Perfect Mother martyrdom," micromanaging their family lives and preventing their husbands (even willing ones) from being equal partners in the home. And while Orenstein reports that single, child-free women seem to grow happier with age, she laments that, for many, their "choice" was thrust upon them, which renders them, in effect, victims of their own ambitions.

Still, while Orenstein makes a strong case for her argument that it is women's own definitions of motherhood (at least as much as men's) that are partly to blame for their lack of progress in the world of work, she does little digging into how companies actually block women's advancement. She notes that having a few women at the top won't change a company's culture. But what can and should organizations do to transform that culture? Will the explosion of women-owned businesses in recent years help foment change?

Orenstein doesn't address those questions, but perhaps the next wave of business books will. And then, finally, we will be done with this genre of play-the-game-like-a-man and use-your-feminine-wiles books at last.

Sidebar: FC Recommends

Work is personal. Work is as much about meaning as it is about money. The team with the clearest sense of purpose wins. These principles have been at the heart of FC's worldview since our first issue. Now comes a book that gives more than 150 people -- including a corporate headhunter, a drug dealer, a marketing executive, a teacher, a supermodel, and a UPS driver -- a chance to speak directly about how and why they do the work that they do. Gig: Americans Talk About Their Jobs at the Turn of the Millennium (Crown Publishers, $25) was assembled by the editors of Web magazine Word.com, who sent interviewers across the United States to capture the spirit of the American workforce. The results, which are published in the form of first-person narratives, are funny, poignant, intelligent, bizarre -- and not to be missed.

Sidebar: Cheat Sheet