The Big Four accountancy giants are the biggest threat to law firms in the future, according to management consultant Michael Roch of Kerma Partners in an article in the Economist. The article states that so far the four have held back from building full service firms and competing for high value work. Instead, they are focusing on work which complements their existing services. 

Annual revenues of $120 billion

The four, Deloitte, EY, KPMG and PwC have combined  annual revenues of $120 billion exceeding the $89 billion generated by the 100 largest law firms combined, the article points out. Sizewise, PwC's law firm is the tenth biggest in the world. It also points out that in the last two years, EY Legal has expanded from 23 countries to 64, merging with a Chinese law firm, Chen & Co, and hiring a partner from Freshfields.  Deloitte has bought Raupach & Wollert-Elmendorff in Germany and PwC recently took over an immigration-law boutique, Bomza, in Canada. Source: Business Insider