This annual report presents the monitoring results of seabird populations and breeding performance throughout Britain and Ireland in 2003 and compares these findings with previous years. The aim of this report is to draw attention to notable changes in seabird numbers or breeding success, which may merit direct conservation action or further research, and to provide valuable feedback by placing results for individual colonies or regions in a wider context. The report is produced in collaboration with the Royal Society for the Protection of Birds (RSPB) and the Shetland Oil Terminal Environmental Advisory Group (SOTEAG).