The dynamics of European market development before the Industrial Revolution are demonstrated to good effect by the Low Countries, which underwent several distinct phases of economic growth between 1000 and 1800. This case study presents a highly illuminating contrast between a considerable degree of economic integration between regions and continuing local variations in the organization of markets. We argue that the relative ease of trade and communication combined with economic competition between towns and regions to produce a fairly rapid diffusion of information, production techniques, legal concepts, and market design from one region to the next. Thus, it was not the early decline of feudalism that stimulated the successive phases of economic growth, but urban competition which produced both a dynamic evolution of contracting institutions and effective constraints on local and central executives. This explains why the political and legal fragmentation of the Low Countries did not end in economic stagnation.