This report is a contribution to the Strategic Environmental Assessment (SEA4) conducted by the Department of Trade and Industry (now Department of Energy and Climate Change). It concerns fish and fisheries of the SEA4 area which covers the area to the west of Shetland and Orkney and most of the UK sector of the Faroe Shetland Channel. Fisheries are very important in the SEA4 area, the mixed demersal fishery for cod, haddock and whiting, the pelagic fisheries for herring and mackerel, and the industrial fishery for sandeel, being the most important. However, there are serious concerns about many fish stocks. This report discusses fish biology, the many different fisheries, trends in fish landings, management efforts to control fishing and achieve sustainable fish stocks, and the interaction between fishing and the oil and gas industry. Relevant aspects of the biology of 28 species or species groups are described. Brief descriptions of the fishery for each species are given, including the method of fishing and long term trends in landings. Statistical information on fish landings available from the International Council for the Exploration of the SEA (ICES) and data for Scottish vessels supplied by Fisheries Research Services are presented. Problems of misreporting and under-reporting are discussed.