The project aims to increase the potential of national sectoral agencies and the Baltic Sea Hydrographic Commission (BSHC) to realize their tasks. BSHC is currently implementing a new and unified height reference system for the Baltic Sea Region (BSR) which is consistent to the European height system EVRS. This means that bathymetric measurements, nautical charts etc., which are needed for safe navigation, offshore infrastructure and sea traffic management, will be based on a so-called geoid model. To this end, detailed mapping of the gravity field across borders, onshore and offshore, is needed. Another target group of these kind of data are the national geological services and the offshore exploration industry. New measurements to modern standards are very costly and time-consuming. In the southeastern BSR data situation and transnational cooperation still need to be improved. In the 60’s to 80’s, campaigns of measurement of the Earth’s gravity have been carried out in the coastal zones of GDR, Poland, Lithuania, Latvia and Estonia, mainly with a support of research infrastructure of the Soviet Union. In a time of independence from the Soviet Union and transformation of the political system, many of these older data remain forgotten or unused. BalMarGrav will build up a transnational network of the relevant experts in the region, save and reprocess the fragmented historical data and provide harmonized and validated open data products to the target groups.