Partners at leading Washington DC firm Swidler & Berlin have agreed to merge with New York's 65-lawyer Shereff Friedman Hoffman & Goodman.
Swidler Berlin Shereff Friedman will have 240 lawyers and boast a turnover of about $110m.
For both firms the merger was driven by changing client demands. Edward Berlin, chairman of Swidler & Berlin, said: "The world is shifting from a regulatory paradigm to a more competitive paradigm. In that environment we needed a capacity for more sophisticated financial and corporate transactions."
He added that with the growth in size of mergers and acquisitions deals and other financial transactions, New York firms were facing an increased need for a sophisticated governmental practice.
Shereffs primarily handles capital markets transactions and securities work.
Berlin said the two firms were not only a natural fit in terms of practice areas but also in terms of firm culture.
"They had to earn each of their clients - as did we," he said. "They share with us an understanding that we are in a service industry."
He believed that some of the older New York firms had yet to adopt this concept.
But Berlin said that "going to New York is a big step" and that the new firm had no immediate plans to set up in Europe.