In the last twenty years a growing literature has shown how much innovation is driven by users. The role of users as innovators is widespread, and can be found also in creative industries. The chapter analyses how users and user communities in particular, enter the innovation process of firms acting in creative industries. User communities have interesting features in that they draw from widespread and highly differentiated knowledge, but are not under the full control of the firm, and need to be carefully managed. The chapter investigates not only what moves users to participate, but also how firms can create strategies to interact with user communities for improving product development and customer support. The literature from a sector re...