Twenty-three State legislatures in 2011 considered bills to permit the carrying of firearms at their public institutions of higher education, and some public colleges in at least six states now allow weapons on college grounds or in college buildings. The lawful possession of guns on campus is a recent and limited phenomenon, but decisions by the Supreme Court, State courts and legislatures, and institutional trustees suggest that many colleges and universities may soon have to decide whether, and under what conditions, firearms will be permitted. This paper summarizes the current situation, analyzes the arguments both for and against weapons on campus, and presents recent data about gun ownership and violent campus crime including murder and manslaughter. It concludes with a discussion of why bitter pro-gun and anti-gun arguments are likely to persist in the future even in the absence of empirical data to support either position. (Contains 3 tables and 17 notes.)