Benjamin Lessing is an assistant professor in the Department of Political Science at the University of Chicago. He studies "criminal conflict"—organized armed violence involving non-state actors who, unlike revolutionary insurgents, are not trying to topple the state. His book Making Peace in Drug Wars: Crackdowns and Cartels in Latin America, forthcoming in the Cambridge Studies in Comparative Politics Series, examines armed conflict between drug cartels and the state in Colombia, Mexico, and Brazil. Lessing is currently conducting fieldwork for his second book, about prison gangs' takeover of urban peripheries in Brazil, El Salvador, and the United States, with support from the Harry Frank Guggenheim Foundation. He has also studied the effects of militarized policing and paramilitary groups' use territorial control to influence electoral outcomes.

Lessing is co-director, together with Paul Staniland, of the Program on Political Violence, part of the Chicago Project on Security and Threats (CPOST).

Lessing received an MA in economics and a PhD in political science from the University of California, Berkeley. He also holds a BA in economics and philosophy from Kenyon College. He completed a postdoctoral fellowship at Stanford University's Center on Democracy, Development, and the Rule of Law (CDDRL) and the Center on International Security and Cooperation (CISAC). Prior to his graduate work, Lessing conducted field research on the small arms trade in Latin America and the Caribbean for numerous international organizations. In addition, he was a Fulbright student grantee in Argentina, Brazil, and Uruguay.