This timely publication follows recent work that the Smith Institute has undertaken on charities, philanthropy and social enterprises. Social enterprises are growing in significance, employing 650,000 people and contributing £8.4 billion per year to the UK economy. Much of the sector’s income now comes from the state to deliver public services. For many, social enterprises have the ability to offer a different approach and ethos, between the profit-driven private sector and the one-size-fits-all public sector. However, the sector is still small and faces capacity and capability constraints. With both main political parties committed to growing the third sector, this collection of essays highlights the challenges and opportunities that lie ahead.