The European Union has agreed that by 2015 where possible and by 2020 at the latest all fish stocks should be exploited at a level that will let them produce the maximum sustainable yield for the long term (MSY). This means taking the highest catches possible without affecting future productivity of the stocks. In the North East Atlantic and adjacent waters (North Sea, Baltic Sea, Skagerrak, Kattegat, West of Scotland Sea, Irish Sea and Celtic Sea), catches are limited to levels based on scientific advice – the means for doing this is by setting total allowable catches (TACs) which are subdivided into national quotas. These set limits on the amount of fish that can be caught and landed.