The main routes of commerce into Asia beyond the frontiers of the Roman Empire are now well charted, thanks to many vindications of the reliability of Ptolemy, and to the archaeological work of Sir Aurel Stein in the deserts of Central Asia and North Arabia. However, little is still known about the administration of this commerce. The classical geographers give very few hints on such questions as who organized and who travelled with the caravans; where were the stages on the route, and how the goods were handed over at each stage; whether currency or barter was used; and what arrangements were made for the security of the traffic.What follows is an attempt to collect the scanty information on these questions in classical sources, and to compare it with what is known about the organization of caravan trade in Asia in medieval and later times. Commerce along three main routes will be considered, the overland trade route from the Aegean to India, outlined by Strabo (after Arternidorus) and Isidore of Charax, the Arabian spice road, and the silk road to China.