The UK Cetacean Strandings Investigation Programme (CSIP) has been running since 1990 and is funded by central Government. We coordinate the investigation of all whales, dolphins and porpoises (collectively known as cetaceans), marine turtles and basking sharks that strand around the UK coastline. As well as documenting each individual stranding, we also retrieve a proportion for investigation at post-mortem to allow us to establish a cause of death. The data and samples collected during the course of our research have also facilitated a large number of international collaborations, which have addressed a wide range of scientific questions.