The EU's Marine Science and Technology programme (MAST) organized a workshop on project data management in June 1997, in collaboration with the Joint Research Centre. The reports given during this workshop have now been published by the European Commission, DG XII, in the volume of proceedings. The importance of harmonizing the collection and handling of ocean data has been realised for almost a century and a half now, with an international conference on the subject held in Brussels as far back as 1853. However, the lack of technology for the processing of ever-increasing quantities of data has meant that the process has been very uneven until recently. In the last couple of decades, data processing technologies have blossomed whilst the capabilities of sensing and transmission systems have also developed hugely. The EU's MAST programme has had a considerable input into recent developments, firstly developing the European Directory of Marine Environmental Data (EDMED) as a starting point for coordinating data, and then developing a policy for project data management. EDMED can be found on the Web at: http://www.nbi.ac.uk/bodc/edmed.html Now, all MAST projects follow a code on data management, and coordination in data management within the MAST programme could now be considered at an advanced stage. Europe-wide support for advice in project data management for marine research projects, including the code, can be found on the Web at: http://www.waterland.net/mast/ The proceedings of the workshop include papers resulting both from MAST projects and from other national or international projects. The book provides a snapshot of the state of project data management at the time of the workshop, and will be of interest to scientists working in MAST projects and other marine science activities. The papers included can be broken down into three categories: generic aspects of data management, experiences from projects, and experiences of data management systems.