In the two decades since the turn of the 21st century, as globalization and technology have restructured nearly every industry, the roster of elite law firms handling the bulk of corporate deal work has undergone a transformation of its own. Firms that were once mainstays at the top of league tables have been surpassed by a set of newcomers, and the London heavyweights that were once power players have largely given way to U.S. competitors. While many firms have retained their competitive edge, as shown by a review of 20 years of mergers and acquisitions league tables provided by Mergermarket and Refinitiv, the law firm hierarchy has been reshaped by the trends of the intervening years.