Since the 1990s, women have made up roughly half of law school classes. Attrition between entry to law firms and partnership results in women comprising 20 and 25 percent of partners. But who makes it to the top of the partnership? Is there yet more gendered attrition? Constructing a unique dataset of publicly-filed M&A deals and detailed biographical information of M&A lawyers, we find that women make up fewer than 10 percent of deal leaders. When we look at the factors that determine who becomes a deal leader we find that credentials – both educational and professional – matter. But they matter more for women. And one credential – attending a top law school – seems to matter a lot. Using conversations with senior lawyers, we try to get at some answers for why.