This is The National Law Journal‘s 30th annual survey of the nation’s 250 largest law firms, covering the period from Oct. 1, 2006, to Sept. 30, 2007. While most of the charts in the NLJ 250 are self-explanatory, here is some information about the process, the criteria and the definitions.

The NLJ sent surveys to approximately 300 law firms and solicited survey submissions to determine the 250 largest. Eligibility is based on a firm’s total number of attorneys, not including contract or temporary attorneys. The cutoff point this year is 172. Also, a firm must have more lawyers based in the United States than in any other single country.