In 1993, the New Zealand Government mandated the requirement that all schools must have in place an ongoing programme of school self-review (Education Review Office, 2000). This thesis identifies the purposes and processes of self-review used in six primary schools in New Zealand. The study also identifies the roles that leaders play in the self-review process and also highlights the impact of teacher research on the process. The research questions are: 1. What are the processes and purposes of self-review in schools and what roles do leaders play in the process? 2. What aspects of teachers' practice have an impact on the self-review process? This research study adopted a qualitative research methodology with semi-structured interviews as the research tool. The qualitative information gathered from the six schools was analysed and written up as a case study. For the purpose of this thesis, self-review is identified as the process of review of all school practices with the intention of improving student achievement. The findings indicated that the main purposes of conducting school self-review were to enhance student achievement, to review school policies and programmes and also to ensure accountability. This study also indicated that through a well-planned process of self-review schools can achieve their goals and fulfill the aims stated in their school charter. Another aspect which participants revealed was that self-reviews result in change and therefore leaders and school staff should have the necessary skills and competencies to deal with and manage such change. This was also identified as an issue of self-review. Participants believed that effective leadership is essential to conduct self-reviews which result in positive outcomes. This study found that the failure to achieve school improvement through self-review, is in part due to the structure of many current self-review programmes. At present, schools perceive self-review as the need to review everything that takes place. This perception may mean that valuable time and money is spent on something that the school does not deem significant. Rather, the findings of this study suggest that concentrating on particular areas for a certain period of time results in a better performance of the whole school. In conclusion, this thesis found that school development and improvement cannot happen without enhancing and focusing on student achievement. For self-review to be successful, it should be carried out in a collaborative school climate of open and honest communication, mutual support and mutual responsibility. For it to be successful, self-review should also be planned, systematic, and ongoing. Data collection for self-review should be done through illuminative, participatory and responsive inquiry methods. Finally, I recommend that further research is needed in the area of self-review and perhaps an exploration of the possible links between a school's decile level and its self-review process.