This paper focuses on illegal drug use and drug dealing in the urban context. It begins with a historical analysis of the drug phenomenon in Portugal and then proposes a methodological discussion about whether or not the ethnographic method is the best empirical research strategy for studying this topic. The main stages and results of two ethnographic studies are then described: the first deals with “freak” youth culture and its use of soft drugs in downtown Porto; the second deals with urban peripheries, the new main areas of hard drug use and street commerce, focusing on the dealer and the junkie whose social worlds, based in psychotropic territories, are described.