This paper is an annual publication issued by the Microeconomic Analysis service of the National Bank of Belgium. The Flemish maritime ports (Antwerp, Ghent, Ostend, Zeebrugge), the Autonomous Port of Liège and the port of Brussels play a major role in their respective regional economies and in the Belgian economy, not only in terms of industrial activity but also as intermodal centers facilitating the commodity flow. This update paper1 provides an extensive overview of the economic importance and development of the Flemish maritime ports, the Liège port complex and the port of Brussels for the period 2005 - 2010, with an emphasis on 2010. Focusing on the three major variables of value added, employment and investment, the report also provides some information based on the social balance and an overview of the financial situation in these ports as a whole. These observations are linked to a more general context, along with a few cargo statistics. Annual accounts data from the Central Balance Sheet Office were used for the calculation of direct effects, the study of financial ratios and the analysis of the social balance sheet. The indirect effects of the activities concerned were estimated in terms of value added and employment, on the basis of data from the National Accounts Institute. (.) After the decline seen in 2009, maritime cargo traffic in the Flemish ports reversed the trend and recorded a rise in 2010. Direct value added increased in each of the four ports in Flanders. Both maritime and non-maritime branches as a whole are up. The only decrease in value added occurred in the maritime branches in the port of Ostend and the non-maritime branches of the port of Zeebrugge. Of the six ports, the port of Brussels recorded the strongest growth rate for value added in the maritime cluster, and the port of Ostend recorded the strongest increase in the non-maritime cluster. Direct employment in the Flemish ports as a whole declined during the year 2010. This is true of both the maritime and non-maritime cluster. ...