On august 9th 1980 the Belgian government took a number of important decisions with relation to the ports of Zeebrugge and Antwerp. The author takes this occasion to analyse and to evaluate the existing seaport policy in Belgium. The first section tries to give an answer to the question: why do public authorities intervene in port activities? Subsequently the article deals with the fundamental data for a port policy until 2000 and with the institutional organisation of this policy. The two last sections present an analysis of the general orientation as far as investment, competition, employment, environment and international relations are concerned. The author arrives at the conclusion that seaport policy in Belgium has to be prepared in a more systematic way and coordinated with other branches of transport, energy and economic policy.