Drunkenness is associated with a wide range of health and social harms, including alcohol poisoning, unintentional injury, violence, sexual assault and public disorder. Whilst the sale of alcohol to people who are drunk is illegal under UK law, public awareness of this legislation and bar server compliance with it appears to be low. In 2015, to address the sale of alcohol to drunks, the Police and Crime Commissioner for South Wales and South Wales Police developed and implemented the Know the Score #drinklessenjoymore pilot intervention. The intervention aimed to increase bar staff and public awareness of the law and promote responsible drinking behaviours in nightlife environments. This report presents an evaluation of the Know The Score intervention which was undertaken to inform the development of the intervention and provide a baseline for evaluating future work