In recent years, researchers have increasingly turned their attention to the proliferation of small arms, a transnational trade amounting to over $7 billion in value during 2002. Small arms are difficult to track and are not the stuff of military parades, but they are immensely destructive. The trade in small arms should be understood not as a market but as a network, one that shares some important properties with networked forms of organization studied by sociologists. I make this argument and then employ quantitative methods developed for the study of social networks in an effort to show the basic structure of both legal and illegal small arms transfers. My analysis is draws from a database that is still in its early stages of development, so the results are preliminary, but they are suggestive and the analytical approach promises to shed considerable light on a corner of the global arms trade that is of great interest to the research and activist communities, and of great consequence to those in war-torn regions of the world.