Book excerpt: Illicit Flows and Criminal Things offers a new perspective on illegal transnational linkages, international relations, and the transnational. The contributors argue for a nuanced approach that recognizes the difference between "organized" crime and the thousands of illicit acts that take place across national borders every day. They distinguish between the illegal (prohibited by law) and the illicit (socially perceived as unacceptable), which are historically changeable and contested. Detailed case studies of arms smuggling, illegal transnational migration, the global diamond trade, borderland practices, and the transnational consumption of drugs take us to Asia, Africa, Latin America, Europe, and North America. They allow us to understand how states, borders, and the language of law enforcement produce criminality, and how people and goods which are labeled "illegal" move across regulatory spaces.