Illegality does not necessarily breed violence. The relationship between illicit markets and violence depends on institutions of protection. When state-sponsored protection rackets form, illicit markets can be peaceful. Conversely, the breakdown of state-sponsored protection rackets, which may result from well-meaning policy reforms intended to reduce corruption and improve law enforcement, can lead to violence. The cases of drug trafficking in contemporary Mexico and Colombia show how a focus on the emergence and breakdown of state-sponsored protection rackets helps explain variation in levels of violence both within and across illicit markets.