The 42nd Congress of WSAVA/FECAVA took place in Denmark from Sept 23-28, 2017. Denmark is the Land of Fairy Tales, a small country measured in acres but large in spirit and history, and the congress was a huge success. Breed–related health comprised a major theme across the meeting. Evidence emanating from the VetCompass Programme of welfare research was cited across many talks and the movement towards accepting primary-care veterinary data as a reliable research resource is now gathering unstoppable pace. Dr Dan O’Neill, RVC companion animal epidemiologist, presented three talks during the congress that explored Feline longevity, the Application of big data and What we know about breed-specific health. "To be or not to be", has long been the Bard’s Danish question but ‘to know or not to know’ has now become the burning VetCompass question.