The international expert meeting “Understanding deep-water biodiversity in the South Atlantic: options for conservation and sustainable use of resources in the high-seas” will consolidate the main scientific findings collected during the South Atlantic MAR-ECO field expedition, a collaborative effort involving scientists from Russia, Brazil, Uruguay and New Zealand. During this 34-day expedition, a team of scientists acquired numerous pelagic and benthic samples over areas of the southern Mid-Atlantic Ridge and the Walvis Ridge. Scientific results emerging from preliminary analyses are already substantial and expected to reveal significant results regarding deep water biodiversity of such poorly studied area. One of the objectives of the workshop is to identify potential ecologically and Biologically Significant Areas (EBSAS) in the South Atlantic based on currently available information and on the recently acquired data. The group will also facilitate the archiving of these scientific records into the OBIS and outline a position paper that will be published by UNESCO-IOC, which will include results from the expedition and an assessment of potential EBSAS in the South Atlantic. Additionally a research proposal will be prepared and submitted to SCOR to enhance networking activities and support continuing sampling in the Deep South Atlantic Ocean. Most importantly, the group will identify research and knowledge gaps in the South Atlantic processes, biodiversity and resources in order to prepare recommendations to be addressed in the framework of our South-South scientific collaboration programme in the South Atlantic, including the ZOPACAS (Zone of Peace in South Atlantic) oceanographic expedition scheduled for the end of this year.