This World Organisation for Animal Health (OIE) Collaborating Centre in Aquatic Epidemiology and Risk Assessment of Aquatic Animal Diseases (ERAAAD) is a joint effort between the Norwegian Veterinary Institute, Oslo, Norway and the Atlantic Veterinary College, Prince Edward Island, Canada. The objective of the centre is to formalize a network of experts and extend knowledge and expertise to OIE and member countries for training and solving health challenges in aquatic species using evidence-based investigation and epidemiologic techniques.