The XX Factor: How the Rise of Working Women Has Created a Far Less Equal World by Alison Wolf Crown, 393 pp., $26.00

In just the past two or three decades, women in more than token numbers have taken their place alongside men at the upper levels of government, the professions, and business. They now earn more than half of all college degrees, and they will shortly make up a majority of lawyers, doctors, and college faculty. While they still account for only a small minority of political and business leaders, that, too, is changing. The rapid ascension of women to the most influential sectors of society—occurring in all advanced Western countries—is likely to have profound implications for public policy, and perhaps even more for the way families construct their lives and raise their children.

In her remarkably wide-ranging book, Alison Wolf describes these women at the top—why their numbers have grown so fast in recent years and what their lives are like. She estimates they make up roughly 15 to 20 percent of working women in advanced countries, or about 70 million women worldwide. (Whether she is defining them by education or income is not clear, but it doesn’t much matter, since the two are so closely correlated.) She calls them variously “professional women” (an unfortunate choice), “graduates,” and the “elite,” but none of those terms quite captures the combination of education, ambition, and professional commitment that characterizes them. Clearly, we need a term that refers to something more than just graduating from college, but it’s hard to come up with one, as Wolf demonstrates. I’ll call them “upper-middle-class,” although that is not very precise either. Whatever the term, if you are reading this, the chances are that you are one of these women or living with one.

The book says relatively little about the other 80 to 85 percent of women, and virtually all Wolf’s interviews are with women in the upper-middle class, mainly her friends and colleagues; and, it seems to me, disproportionately women in business or finance. But that is a small cavil (mainly with the subtitle, which seems to promise a focus on all working women) in a book that is so interesting and well documented, drawing on a variety of surveys as well as interviews. Moreover, the focus on upper-middle-class women seems justified, since their rise to the top is a new and largely unexamined phenomenon. Despite the mountain of data Wolf amasses, however, she does not say very much about what she thinks the reader should conclude from all of it. I will try to draw some conclusions here, based on her book, on other publications, and on my own experiences.

Until the 1960s, with few exceptions, the only way even educated women could gain security, let alone status, was to…