For several decades, one of the major issues facing Australia’s health sector has been a shortage of nurses; a trend also evidenced across many other Organisation for Economic Co-operation and Development (OECD) countries. Without a suitably sized nursing workforce, a society’s ability to care for the population is diminished, and will continue so unless this trend is reversed. One of the factors contributing to this shortage is the poor retention of currently employed nurses, which results from, in part, a high proportion of nurses lacking commitment to their organisations. For public sector hospitals, the largest employer of nurses in Australia, this lack of organisational commitment is a continuing concern that impacts upon the ability of health organisations to provide care to patients. This thesis examines the factors that impact upon nurses’ commitment to their organisations. A theoretical framework, Social Capital Theory (SCT), was used as a lens through which to view the behaviour of nurses. The reason for this choice of theory is that SCT is used to examine the relationships in the workplace by exploring their quality, structure, and the context in which they operate. This research uses the SCT framework to interpret how relationships impact upon nurse outcomes, including their level of role ambiguity, the extent to which they perceive that they are empowered in their work, and most importantly, their organisational commitment. Of particular interest to this study is the difference between these organisational practices and the organisation’s espoused policies, to identify gaps and areas for improvement. The research used a sequential mixed methods approach. Four methods of data collection were used comprising surveys, focus groups, interviews, and document analyses, so as to examine the relevant issues from a variety of viewpoints and triangulate data. Respondents comprised nurses working in two public sector hospitals located in Australia. The data includes 167 surveys, 12 focus groups and 17 interviews. Analysis of the quantitative data involved using regression analysis and path analysis, while the qualitative data were analysed using manifest and latent content analysis.