In response to the central position social capital has come to occupy in discourse about the social and economic well-being of individuals, families and their communities, this paper first examines how the concept of 'social capital' features in current public policy and welfare reform, and, second, draws upon available Australian and overseas research to provide analysis of how well the concept might meet policy expectations of it. In doing so the paper highlights some lessons about the social capital/ social security nexus which have implications for the ongoing role of government in the provision and regulation of Australian social security.