Fought when radio was first introduced, the Press-Radio war was an attempt on the part of print journalists to block the emergence of radio news. For nearly a decade, the newspapers of America fought to keep broadcast journalism off the air, exerting various forms of economic, regulatory, and legal pressure against new competitors. This study traces the stages and forms of institutional self-defense utilized by the press. Far more than mere battles to protect profits, media wars are fights to preserve the institutional power that derives from controlling the channels of communication.