Social housing policy in the UK mirrors wider processes associated with shifts in broad welfare regimes. Social housing has moved from dominance by council housing provision to the funding of new investment through voluntary sector housing associations to a greater focus on the regulation and private financing of these not-for-profit bodies. If these trends run their course, we are likely to see a range of not-for-profit bodies (council, arms-length management bodies and different forms of housing association) providing non-market housing in a highly regulated quasimarket strongly shaped by commercial considerations and the statutory requirements levied on them by Government and regulatory agency alike. In this paper we examine these issues through the lens of neo-institutional economics, which we believe can provide important insights into the fundamental contractual and regulatory relationships that are coming to dominate social housing from the perspective of the key actors in the sector (not-for-profit housing organisations, their tenants, private lenders and the regulatory state). The paper draws on evidence recently collected from a study evaluating more than 100 stock transfer organisations that inherited ex-public housing in Scotland, including 12 detailed case studies. The focus of the empirical material is the operation (and performance thereof) of these (often new) organisations in a challenging regulatory environment while seeking to provide tenant involvement in decision-making, contribute positively to community development, retain pledges on rents, repairs and investment, work within tough sale and purchase agreements and manage a long term debt-funded business plan. This material also allows us to reflect further on the implications for the future of the sector in a context of the reasonable expectation of many more new social landlords, statutory housing standards, a strong if not an onerous regulatory framework, pricing and benefit reforms, preference-based allocations systems and common housing registers. The paper concludes that social housing stakeholders need to be aware of the risks (and their management) faced across the sector and that the State needs to have clear objectives for social housing and coherent policy instruments to achieve those ends.