This chapter summarises the recurring themes and lessons from the preceding substantive chapters and reflects upon their implications for public policy and analysis. The chapter argues that social innovations provide many examples of imaginative and inspirational responses to the serious challenges confronting national welfare systems. The energy and commitment of social innovations are admirable, and their participatory approach to policy development and delivery, which empowers service users, is particularly valuable. However, the chapter notes that it is often difficult to evaluate the impact and relative cost-effectiveness of social innovations. Many have diffuse aims and multiple objectives. Also, as many social innovations operate at a local community level, they address the manifestations rather than the structural causes of problems. The chapter concludes by suggesting that most social innovations operate within rather challenge their existing socio-economic infrastructure and political environments. Currently they may complement but cannot replace existing public welfare systems.