Paper presented at Understanding Shipping Markets, International Association of Maritime Economists (IAME) Conference, Copenhagen, Denmark, 24-26 June 2009International audienceSeaports are key locations within value chains and production networks. Port policies of national and local governments seek higher rents through strategies of specialisation or diversification. Elaborating on longstanding research about urban and regional development, this paper proposes an empirical investigation of the interplay between traffic variety and port performance. The analysis of traffic data per commodity for 330 European ports highlights the influence of multiple factors such as location, function, and local context, together with the specificity of so...