Mass shootings at a Connecticut elementary school, a Colorado movie theater, and other venues have prompted a fair number of proposals for change. Advocates for tighter gun restrictions, for expanding mental health services, for upgrading security in public places, and, even, for controlling violent entertainment have made certain assumptions about the nature of mass murder that are not necessarily valid. This article examines a variety of myths and misconceptions about multiple homicide and mass shooters, pointing out some of the difficult realities in trying to avert these murderous rampages. While many of the policy proposals are worthwhile in general, their prospects for reducing the risk of mass murder are limited.