Therese Pritchard and Lisa Mayhew

Bryan Cave chairwoman Therese Pritchard had done her research on Berwin Leighton Paisner, reading up on the British firm’s practice groups and culture, before she reached out to her transatlantic counterpart Lisa Mayhew.

Their first meeting, in London, went smoothly enough that Mayhew invited Pritchard to meet again to discuss the possibility of a combination. Their next meeting would be in Berlin, a location chosen by Mayhew to keep their merger consultations cloaked in secrecy, likely informed by BLP’s previous tie-up talks with Greenberg Traurig becoming public before eventually fizzling out. One of the first things the two women agreed on was a desire to combine their firms under one profit pool, eschewing the more popular Swiss verein model.

On Tuesday, Bryan Cave and BLP accomplished that task as Bryan Cave Leighton Paisner officially goes live with Pritchard and Mayhew as co-chairwomen. The combined firm now has more than 1,600 lawyers, roughly $900 million in annual gross revenue and represents more than half of the world’s 100 largest companies.

The merger between Bryan Cave and BLP is unique in at least two respects: The combined profit pool, and the fact that both legacy firms were run by women. In both the U.K. and the U.S., women firm leaders remain a small minority, a continuation of women making up ever-smaller proportions of lawyers as they move up the law firm hierarchy.

In 2015, The Lawyer reported that eight of the 50 largest U.K. firms—16 percent—were led by women. Five women hold the chair or managing partner title among the 50 largest firms in the U.S. Bryan Cave Leighton Paisner said it would be the first global firm to be co-chaired by two women in Mayhew and Pritchard.

“From the first conversation, it was an unusually good fit and a good connection between the two of them,” said Kent Zimmermann, a consultant at The Zeughauser Group who advised BLP on the merger. “They’re like-minded on many issues, from innovation on down. And I think their relationship is not as typical as people might think.”

Mayhew said in an interview that she and Pritchard quickly developed “good personal chemistry.” But both women were quick to point out that the merger was the result of hard work by large teams at both Bryan Cave and BLP.

“It was quickly apparent to both of us that there was the potential for shared strategic ambition, and we had similar ways about doing business in terms of the way we go about serving our clients,” Mayhew said. “And right from the beginning, the notion of potentially putting the two law firms together as one single-structure firm and nonverein was something we discussed right in those very first meetings and throughout.”

Pritchard and Mayhew said they believe a financially integrated firm gives partners more incentives to share clients and work across geographic boundaries. With a long-standing motto of “one firm,” Bryan Cave has held itself out as a place where clients will get the best lawyer handling their matters. BLP has a similar culture dating back to the merger that created it in 2001, when Berwin Leighton and Paisner & Co combined starkly different compensation systems. (Stanley Berwin, an English solicitor who died 30 years ago, will see his name disappear from the new firm’s shingle.)

To accomplish an integrated firm through the latest merger, the talks took longer than some expected after both firms confirmed their discussions last October. Tax complications related to integrating the two firms into one financial unit required bringing in consultants from global accounting giant Deloitte. Pritchard said she and Mayhew worked together to find ways to overcome hurdles like that throughout the process.

“Our perspective on the negotiations has been that, when there’s an issue, we work together on how we can solve it,” Pritchard said. “At the end of the day we both knew it was our job to represent our respective partnerships to the best of our abilities, but there was also a real attitude that we could come up with compromises to solve problems.”

Starting Monday, the two will take that approach to work for the same partnership.