In the last decade, successive UK governments have pursued an agenda of opening up public services to alternative providers from the private and third sectors, with the stated aim of diversifying provision in order to promote competition, efficiency and innovation. The current coalition government has made a particular commitment to “support the creation and expansion of mutuals, co-operatives, charities and social enterprises and enable these groups to have much greater involvement in the running of public services”. With an annual spend of £230 billion, public sector procurement has the potential to create significant business and growth opportunities for social enterprises. There is a huge diversity of products and services that social enterprises may be able to supply to the public sector; in recent years there have been particular opportunities in the areas of health, social care and youth provision. And social enterprises can be sources of creative and innovative approaches to service provision. But how easy is it for social enterprises to actually bid for and win public sector contracts? If social enterprises are locked out of procurement processes this can close off one potential path to innovative services. This case study report examines some of the barriers social enterprises face in contracting with the public sector.