Sean Casey, a partner at Walden Macht & Haran and a former assistant U.S. attorney at the  Department of Justice, said the 40-lawyer New York City firm has average profits per partner in the Am Law 100 range despite its size.

In addition to all the traditional metrics, its compensation model rewards collaboration and collegiality. Bonuses bring the salaries of the highest-performing associates above New York market rates, he said.