Marcus Reckermann is the head of the International BALTEX Secretariat at Helmholtz-Zentrum Geesthacht (HZG), Germany. As a biological oceanographer, he has participated in research cruises in the Baltic Sea, North Sea, North Atlantic and Arabian Sea, and published several papers on marine biogeochemistry. His current work involves the editing of scientific books and reports (e.g. the BACC book), and the organization of workshops and conferences. The International BALTEX Secretariat represents the administrative support of the scientific BALTEX community. Keith Brander is a senior researcher at the Technical University of Denmark, Charlottenlund. His expertise ranges from fish population dynamics and fisheries management to plankton and marine ecosystems, with an emphasis on environmental effects. Recent interests are in detecting climate change impacts, resolving conflicting objectives for biodiversity and food production, and helping fisheries and marine ecosystem management to adapt to the impacts of climate change. He was lead author on fisheries and marine ecosystems for the fourth IPCC report. Brian R. MacKenzie is a professor for marine fish population ecology at the Technical University of Denmark, Charlottenlund and at the University of Copenhagen, Denmark. His research interests include natural and anthropogenic (climate change, fishing) effects on fish populations and marine ecosystems. Recently, he has been working on climate change effects on cod and its habitat throughout the North Atlantic, including the Baltic Sea. Anders Omstedt is a professor at the University of Gothenburg, Sweden. His main research interests have been the ocean climate and the physics of ice covered water bodies, in particularly the Baltic Sea and the polar oceans. His recent research work is oriented towards climate change and modelling of coupled physical-biogeochemical systems, including the carbon cycle. He has been involved in the BALTEX programme from its very beginning.