According to Laura D'Andrea Tyson, Dean of the College of Business at London Business School, in both the United States and Europe women often choose to opt out of high-powered jobs. In her words: "The opt-out hypothesis could explain why, according to a recent U.S. survey, 1 in 3 women with an MBA is not working full-time, versus 1 in 20 men with the same degree. Today, many companies are recruiting female MBA graduates in nearly equal numbers to male MBA grads, but they're finding that a substantial percentage of their female recruits drop out within three to five years. The vexing problem for businesses is not finding female talent but retraining it." 164 In your opinion, how large is the opt-out phenomenon, what are its causes, and what can companies do to retain talented women?