Mergers, acquisitions, division and reorganizations occur between law firms as in other businesses. The specific books of business and specialization of attorneys as well as the professional ethical structures surrounding conflict of interest can lead to firms splitting up to pursue different clients or practices, or merging or recruiting experienced attorneys to acquire new clients or practice areas. Results often vary between firms experiencing such transitions. Firms that gain new practice areas or departments through recruiting or mergers that are more complex and demanding (and typically more profitable) may see the focus, organization and resources of the firm shift dramatically towards those new departments. Conversely, firms may be merged among experienced attorneys as partners for purposes of shared financing and resources, while the different departments and practice areas within the new firm retain a significant degree of autonomy.
Law firm mergers tend to be assortative, in that only law firms operating in similar legal systems are likely to merge. For example, U.S. firms will often merge with English law firms, or law firms from other common law jurisdictions. A notable exception is King & Wood Mallesons, a multinational law firm that is the result of a merger between an Australian law firm and a Chinese law firm.
Though mergers are more common among better economies, slowing down a bit during recessions, big firms sometimes use mergers as a strategy to boost revenue during a recession. Nevertheless, data from Altman Weil indicates that only four firms merged in the first half of 2013, as compared to eight in the same period in 2012, and this was taken by them as indicating a dip in morale regarding the legal economy and the amount of demand.