Objectives: To determine the incidence and severity of injuries and illnesses incurred by a professional America's Cup yacht racing crew during the preparation for and participation in the challenge for the 2003 America's Cup. Methods: A prospective study design was used over 74 weeks of sailing and training. All injuries and illnesses sustained by the 35 professional male crew members requiring medical treatment were recorded, including the diagnosis, nature, location, and mechanism of injury. The volume of sailing and training were recorded, and the severity of incidents were determined by the number of days absent from both sailing and training. Results: In total, 220 injuries and 119 illnesses were recorded, with an overall incidence of 8.8 incidents/ 1000 sailing and training hours (injuries, 5.7; illnesses, 3.1). The upper limb was the most commonly injured body segment (40%), followed by the spine and neck (30%). The most common injuries were joint/ ligament sprains (27%) and tendinopathies (20%). The incidence of injury was significantly higher in training (8.6) than sailing (2.2). The most common activity or mechanism of injury was non-specific overuse (24%), followed by impact with boat hardware (15%) and weight training (13%). "Grinders" had the highest overall injury incidence (7.7), and "bowmen" had the highest incidence of sailing injuries (3.2). Most of the illnesses were upper respiratory tract infections (40%). Conclusions: The data from this study suggest that America's Cup crew members are at a similar risk of injury to athletes in other non-collision team sports. Prudent allocation of preventive and therapeutic resources, such as comprehensive health and medical care, well designed conditioning and nutritional programmes, and appropriate management of recovery should be adopted by America's Cup teams in order to reduce the risk of injury and illness.