The scientific evidence is now overwhelming that climate change is a serious global threat which requires an urgent global response, and that climate change is driven by human activity. The IPPC Report (2007) states that sea levels will rise by 3.1 cm every decade; the oceans have warmed to a depth of 3 km; Arctic summer sea-ice is likely to disappear in the second half of this century; up to 40% of species could face extinction; weather patterns will become more extreme; for example hurricanes and storms will become more intense. The Stern Review (2006) estimates the social and economic cost of climate change to the global economy at € 5,500 billion by 2050. The Stern Review concludes that, provided we take strong action now, there is still time to avoid the worst impacts of climate change. Enough is now known to make climate change the challenge of the 21st century, and the research community is poised to address this challenge. The need for enhanced detection and assessment of the impacts of climate change on the oceans and their ecosystems has been emphasised in several recent publications (Stern 2006; Hoepffner, N et al. - JRC-IES 2006; IPCC 2007). Europe is warming at a faster rate than the global average, and the physical attributes of our seas are changing accordingly, with implications for the functioning of our regional climate and our marine environment. Therefore, in addressing the impacts of climate change on the oceans, Europe must pay particular attention to its regional seas. The diverse nature of Europe’s regional seas, with the attendant diversity of expression of climate change impacts, represents a particular challenge for monitoring and management of climate change at the pan-European, regional and local levels. The changes in the marine environment will have a profound impact on the daily life of Europe’s inhabitants, requiring forward planning in preparation for the changes. It is hoped that the report will contribute to this planning. In 2005 the Marine Board established a working group of experts from different countries and disciplines, under the chairmanship of Dr Katja Philippart (NIOZ, the Netherlands), to address climate change impacts on the marine environment, with the objective of documenting the existing knowledge on, and implications of, climate change, with particular reference to regional priorities and dimensions. The report of the Working Group profiles an overview of the research needs and future scientific challenges of climate change at the both European- and regional-seas level, including the Arctic, Barents Sea, Nordic Seas, Baltic, North Sea, Northeast Atlantic, Celtic-Biscay Shelf, Iberia upwelling margin, Mediterranean and Black Sea. The report identifies future research challenges in terms of climate change monitoring, modelling, and development of indicators. Its conclusions will support the development of future research strategies and inform the development of policy. Throughout this position paper, ‘climate change’ is used to denote the recent predominantly human-induced change (principally the result of greenhouse gas emissions but also from urbanisation and deforestation) and climate variability due to random processes and natural causes such as volcanoes, solar radiation, and non-linear interactions between ocean and atmosphere (Hasselmann 1976).