Social scientists draw important lessons for modern development from the medieval Maghribi traders who, it has been argued, lacked effective legal mechanisms for contract enforcement and instead relied on informal sanctions based on collective ostracism within an exclusive coalition. We show that this claim is untenable. Not a single empirical example adduced as evidence of the putative coalition shows that a coalition actually existed. The Maghribi traders made use of the formal legal system in order to enforce agency agreements in long-distance trade. A subset of the traders did form a web of trusted business associates that contributed to informal contract enforcement, but this was very different from the hypothesized coalition, in neither being exclusive nor having a clearly defined membership. The Maghribi traders combined reputation-based sanctions with legal mechanisms, in ways that resemble the practices of medieval European merchants. We find no evidence that the Maghribi traders had more ‘collectivist’ cultural beliefs than their European counterparts.