This chapter discusses attempts to involve stakeholders in the co-production of Future Internet (FI) services in a smart city living lab. We outline the experience of five European cities using an open innovation approach to citizens’ engagement in the co-production of smart city services. Recent practice and emergent trends in five urban ecosystems, called ‘Arenas’, are analysed by drawing on the results of detailed case study research. These results are set against ‘good practice’ expectations about how co-production should occur as set out by the European Network of Living Labs as well as in open innovation strategic policies. Based on the case studies, a set of propositions are explored about what needs to be done to build the stakeholder innovation networks required to shape future smart cities. The study suggests that if smart cities are to deliver a better quality of life in more attractive urban areas, new ways of engaging with the stakeholders are necessary to provide them with not just better access and inclusion but also to empower them to act as a catalyst in transforming the dynamics of city services as well. In light of the demands of delivering the FI, cities also need to redefine what they mean when they claim to be a ‘smart’ city and to reconfigure what they take to be the underlying role of stakeholder engagement in service co-production.