Eighty years ago, Congress enacted the Foreign Agents Registration Act (“FARA”), requiring “foreign agents” to register with the Attorney General. As amended over the years, it applies broadly to anyone who acts on behalf of a “foreign principal” to, among other things, influence U.S. policy or public opinion. Until recently, it was a backwater of American law—and a very still backwater at that, with just seven prosecutions over the last half century.

That is changing now. Like the once obscure Foreign Corrupt Practices Act, which prosecutors revived from hibernation a decade ago, FARA may be ready for its close-up. In this guide, we identify the key points and provide a detailed primer on FARA registration, highlighting the ways in which it is now relevant to a broad cast of characters, including multinational corporations.