Gun ownership has been mentioned for some time in relation to situational crime prevention.' Empirical research, however, has provided rather weak and inconsistent support for increased gun control efforts.2 One reason may be that it has focused on cross-sectional analyzes in the United States3 or on evaluations of specific gun control measures over time. of guns in some states or counties.4 The difficulty with such research projects is that neither strict gun control nor the passage of a new law in some states necessarily affects the number of guns in the hands of citizens, since in most in some cases the weapons continue to be sold in neighboring states. This is well illustrated by the limited variation in the prevalence of gun ownership across regions of the United States: 29% of households in the East, 44% in the West, 46% in the Midwest, and 54% in the South. government might not affect gun availability or violent crime rates. Gun ownership rates tend to vary much more between countries than within them. However, international research has been relatively informative...