ProPublica Lobbying Registration Database Updated daily. By Jeremy B. Merrill

“It can seem like lobbyists run Washington from behind the scenes. But their work isn’t completely opaque. They’re required to register with the House and the Senate when they lobby for a new client. Former members of Congress, former congressional staffers and former high-level regulators who now work as lobbyists—the so-called “revolving door” — are required to disclose their “covered” former positions. You can use this database to find out who’s lobbying on whose behalf — and about what issues. Here’s a guide.