Partywise is a prevention concept using a campaign and other materials to inform and sensitize clubbers, and brochures, materials and training sessions for prevention workers and nightlife professionals. Partywise aims to encourage partygoers to be responsible during a night out. It tries to inform and sensitise clubbers in different ways, so that they can make responsible choices.The process evaluation showed a very positive result for the different aspects of Partywise. In general, clubbers liked the look and feel of Partywise and could understand the information dissiminated. The majority of clubbers thought that initiatives like partywise were nessesary.Partywise is a useful project to inform and sensitise young party people about health risks in nightlife environments. It is not currently known whether people change their behaviour as a result. However, through Partywise, revellers know what the risks are and can choose for themselves if they want to take these risks or not.