Our question was simple. After years of measuring women’s success in law firms primarily by the percentage of female equity partners, we wanted to use a more exacting standard. We wanted to know: How many women partners had advanced to the highest ranks of law firm hierarchies?

To that end, we asked each firm in The Am Law 100 to list the women partners serving in their firm’s highest leadership positions—as firmwide managing partners or chairs, as members of a chief governing body or a compensation committee, as head of a practice or an office. After a fair amount of pestering, 93 firms in The Am Law 100 responded. Their answers were not surprising. There was a smattering of firms that stood out for their higher proportion of women in top leadership roles—a group that included Fulbright & Jaworski, Reed Smith, and Shook, Hardy & Bacon. These outliers had female partners who represented more than a third, or even half, of a governing or compensation committee, and they did so with a critical mass of three or more seats. But for most of the rest, the numbers of women leaders were depressingly similar.