To address environmental and sustainability problems we need a new way of educating our young people; one that provides them with the capabilities and skills to find and examine their own frameworks for solving these problems in the future. Thus, it has been argued that we urgently need to find new models and approaches to education that reflect and contribute to sustainable practices, as traditional educational systems have contributed to the unsustainable conditions we now face. A whole school approach to education for sustainability (EfS) supports the notion that children learn both through an enacted curriculum and informally through the messages and meanings inherent in their surroundings. A whole school approach to EfS involves transforming the system rather than reforming it or simply accommodating change. One school-focussed programme that has been fostering such whole school approaches in New Zealand is the Enviroschools programme. The Enviroschools programme supports a whole centre/school approach to EfS, and describes four key areas of schooling life that have an effect on sustainability and student learning: (1) People (and Participation); (2) Programmes; (3) Practices; and (4) Place. This thesis has examined the development of a whole school approach to EfS by investigating the planning, implementation and outcomes of such an approach in a New Zealand primary school. An interpretive methodology was used to guide data collection through observations, interviews and analysis of student work as an Enviroschools facilitator worked with the staff and students of the school during their first year of integrating EfS into their school. An analytical framework, based on themes emerging from the ‘People, Programmes, Practices and Place’ dimensions of a whole school approach to EfS, was used to interpret the data arising from this single, case study school. This study found that the school leader(s), such as the Principal, have a profound effect on the success of the integration of the whole school approach to EfS. It also found that teacher knowledge and understanding of the complexity of EfS is key to successful integration into the curriculum, with particular emphasis on its transdisciplinary nature. In addition, special attention needs to be paid to the nature of EfS Facilitation and the interface between EfS theory and practice, for example, how to practically involve the ‘whole school’ in EfS participation. This research may assist schools in their own EfS journeys by providing insight and clarity around the process of development of a whole school approach to EfS. Detailing the factors that enable and inhibit the development of a whole school approach may provide schools with the direction needed to avoid possible pitfalls, and focus on factors that progress the development of EfS in their school.