Medieval commercial transactions did not occur spontaneously. They were crafted by merchants with the support of numerous personnel on the medieval marketplace: notaries, innkeepers, brokers, transporters, and subordinate personnel of the merchant's entourage. This study introduces the reader to the challenges of trade in the Mediterranean world and to specific market conditions in the Mediterranean French town of Montpellier. A case study of the business of the Cabanis merchants permits an in-depth examination of the facilitation of trade by intermediaries whose activities are traced in the discovery phase of arranging a deal and in its closing and execution. Medieval business practice involved multiple layers of personnel. The complexities of medieval trade are revealed in the new emphasis given to those who assisted merchants in their commercial endeavors.