Gambling has been Macau’s principal industry and a major source of income for the city for nearly 180 years. However, surprisingly little has been said about its urban impact and connections to a wider economy of vice, e.g. opium, pawnbroking and prostitution, which was consolidated in the second half of the nineteenth century mostly by the hands of a Chinese entrepreneurial elite. This article takes a novel approach to examining Macau’s early colonial development by historicizing the city’s modern economy in its urban form. It shows that the development of vice businesses promoted the diversification of commercial activity, real estate development and the creation of public facilities, defining a type of ordinary urbanization, business-led rather than government-oriented, that affected Macau’s urban character and identity in durable ways.