There’s lobbying, and then there’s influence. Law firms in Washington, D.C., are finding both fields increasingly lucrative.

For its Influence 50 survey, our sibling publication The National Law Journal tracks law firm revenue derived from traditional lobbying work in the government’s legislative branch and before some political appointees. This year, the NLJ asked firms to measure their public policy work more broadly, so that it focuses more on their nonlitigation regulatory activities.