The US’s top 100 law firms have capped off a record-breaking five-year run that has seen partner profits soar and combined fees last year hit $64.5bn (£32.4bn), according to the definitive snapshot of the world’s largest legal market.

The American Lawyer‘s eagerly-awaited top 100 rankings confirm that the M&A boom of the first half of 2007 has driven the US’s top law firms to record financial results.