The ARCTOS research network was established in 2002 after the initiative from scientists at The Norwegian College of Fishery Science/University of Tromsø¸ (UiT), the Norwegian Polar Institute, UNIS (The University centre at Svalbard) and Akvaplan-niva. Later, scientists from the Institute of Geology (UiT), the Institute of Marine Research and BodÃ¸ University College have joined, as well as scientists in several other institutions in Norway. ARCTOS is organized with a secretariat at UiT, and with part of its administrative activities localized at UNIS, Akvaplan-niva and IMR. The ARCTOS scientists conduct science over a broad range of marine ecology topics in the Barents Sea and around Svalbard, and in most of the northern waters. Several important institutions in Russia, North America and the EU are collaborating within the frame of ARCTOS, giving this research a pan-Arctic perspective. Research on the Norwegian side is financed through the Norwegian Research Council, EU-programmes, own institutional funding and support from the petroleum industry (StatoilHydro, ConocoPhillips, Eni and Total). ARCTOS is organised as a resesarch project based at the University of Tromso.