This paper explores the implications and uptakes of game developers’ increasing reliance on the creative labour of fan content creators. It draws on an ethnographic account of Australian game developer Auran’s increasing reliance on train and rail fans in the process of developing Trainz: a train and railroad simulation. I argue that this is not simply a case of the exploitation of unknowing fans as a source of free labour. This research demonstrates that gamers are not only well aware of these practices; they are also sophisticated practitioners who participate in them. These complex entanglements of the proprietary and the non-proprietary, the commercial and the non-commercial, are not necessarily an appropriation of fandom by corporate bottom-line agendas. However, Auran’s effort to integrate fan content creation into the commercial game development process struggles with the problem of fundamentally reorganising the project to support this kind of collaborative work. Keyword...