This paper analyzes the technical efficiency and technological change of Portuguese seaports. Depending on the managerial procedure adopted by management, improvements or deterioration of efficiency can be induced. In order to analyze the efficiency of the aforementioned activity, a benchmark procedure is employed: data envelopment analysis (DEA), which permits the separation of total productivity into technical efficiency and technological change. It is found that the seaport authorities, which are state-owned but in some cases have private exploration, did not achieve total productivity improvements in the period considered, with most of them achieving improvements in technical efficiency, but not all advancing in technological change, thus denoting that there is room for further improvement in this activity.