The concept of social capital has received increasing attention in recent years from both academics and the policy community. It has come to be widely used in debates about housing and neighbourhoods and figures strongly in discussions of social cohesion, community development and neighbourhood renewal. This paper provides an original discussion of some of the key issues related to these debates. It argues that, although it is widely used, the concept of social capital is poorly defined and much of the discussion is based upon assertion rather than upon evidence. The paper goes on to present the results from original social survey work carried out in Bournville in Birmingham, England, and referring to different parts of the Bournville estate. The results refer to the extent of bonding, bridging and linking social capital and how these relate to the social and economic differences between six neighbourhoods within Bournville. The survey evidence is not consistent with key assertions made in the existing literature in relation to age, poverty and class and the paper concludes by raising important reservations about the use of social capital as an analytical rather than a generic concept.