The accounting profession hasn't gotten to where it is by resting on its laurels. For years, the Big Five firms have known that it is less expensive and more efficient to have lawyers on staff rather than engage lawyers outside the firm.
Now, someone has actually counted the numbers and the Big Five wins! When you add up all of the Big Five firms and affiliate lawyers, there are more attorneys in accounting firms than the world's largest law firms.
There are a few areas that are worth observing, too. For example, lawyers within Big Five firms also are expanding at a very fast rate, and globalism is paramount in importance as the large accounting firms seek world-class status.
However, there is one area that the Big Five doesn't own, and that's practicing law in the United States, given the rules of multidisciplinary practices. This could change some time in the future as state bars are continuously investigating the possibility of relaxing the rules.