Ports were nodal points in networks, and their activities and comparative success must be comprehended in this light. This paper focuses on three sets of network relationships that were instrumental in determining the fate of modern ports: networks with hinterlands, networks with forelands, and the networks that joined user businesses and port authorities. The comparison concerns seven of the eight major ports of Western Europe in the twentieth century: Hamburg, Rotterdam, Antwerp, London, Liverpool, Le Havre, and Marseille. In each case, the strength, weakness, or withering of networks help explain why certain ports (Hamburg, Rotterdam, and Antwerp) were enduring successes, why others (Le Havre and Marseille) began to fade, comparatively, by the early part of the century, and why still other ports (London and Liverpool) enjoyed great success, but then crashing falls from front rank positions, particularly following containerization.