Ancient Roman trade was severely hampered by slow transportation and by the absence of a state that helped traders enforce their contracts. In Trading Communities in the Roman World: A Micro-Economic and Institutional Perspective Taco Terpstra offers a new explanation of how traders in the Roman Empire overcame these difficulties. Previous theories have focused heavily on dependent labor, arguing that transactions overseas were conducted through slaves and freedmen. Taco Terpstra shows that this approach is unsatisfactory. Employing economic theory, he convincingly argues that the key to understanding long-distance trade in the Roman Empire is not patron-client or master-slave relationships, but the social bonds between ethnic groups of foreign traders living overseas and the local communities they joined.