The goal of universal state provision of social services will long continue to elude most developing countries. Formidable challenges posed by high mortality rates, low literacy, poor sanitation and limited access to safe drinking water, raise important policy questions concerning the appropriate blend of public and private provision. Should the state’s role be relegated to that of residual provider for those excluded from access to private provision? How can the state effectively regulate and monitor the private sector? What kinds of partnership can it enter into with private providers and non-governmental organisations (NGOs)? How can NGOs and other groups in civil society hold public and privat providers accountable for the quality and coverage of services? This issue of Insights probes these issues by reference to examples from around the world of novel public-private partnerships for healthcare, education and the management of urban wastes.