The US competition agencies – the Antitrust Division of the Department of Justice (DOJ) and the Federal Trade Commission (FTC) – often share jurisdiction with sectoral regulators also charged with fostering competition, such as the Federal Communications Commission (FCC). This article highlights how this institutional structure – concurrent jurisdiction – helps protect competition through the lens of recent US experiences involving the communications industry. It argues that concurrent jurisdiction is likely most effective when the communications regulator has independent access to industry information to limit capture, when the communications regulator can take a long-term perspective, when the antitrust agency can focus on competition as its sole goal, and when senior appointments at the two agencies are made with coordination between them in mind.