This thesis describes and examines research carried out by Taylor Baines & Associates on the social impacts of selected New Zealand prisons on their host communities. Specifically, this thesis aims to provide an insight into social assessment in practice, describe and discuss practicerelated issues that arose, and explore issues associated with the use of social assessment as a tool for assessing the social impacts of existing projects or policies, as opposed to a tool for assessing the potential social impacts of proposed projects or policies. Taylor Baines' prison research was part of a wider government funded research programme, which investigated the social impacts of solid waste, wastewater, prison, and retail facilities on their host communities. The research on prison facilities included a series of four case studies, which investigated the impacts of Rolleston Prison near Christchurch, Rimutaka Prison in Upper Hutt, Hawkes Bay Prison near Hastings, and Wanganui Prison near Wanganui city. The case studies revealed a range of social impacts (both positive and negative), and highlighted a number of implications for the siting, planning and management of existing and future prisons. As a key researcher involved in Taylor Baines' research, this thesis enabled the author to provide insight into the approach, process and method used. This insight includes discussion of a number of practice-related issues. One of the key issues to emerge was how to define the concept of 'host community'. The examination of this issue reveals contrasting approaches to its definition, and varying implications for method selection, research findings, and utilisation of research by end users. Another key outcome of this thesis is the proposal for an alternative social assessment process - a process that can be used to assess the social impacts of existing projects and policies.