This thesis reports on a study of academisation as a dynamic process of systemic change. In order to examine and exemplify the associated debates and discourses, I conducted empirical research based on a school in England. I studied how a proposal for structural change was explained, justified, planned, implemented and understood by the actors involved. Over a period of eighteen months, I generated data from interviews, documents and observations. I begin by setting out the key debates and policy shifts that have contributed to the development of academisation in England, which I present as a complex of related initiatives. I then report and theorise on my fieldwork in three journal articles and one book chapter. The first output, Theorising systemic change: lessons from the academisation project in England, argues that the âenactmentâ of academisation should be regarded and researched neither as a policy nor as a complex of policies, but as a process of system redesign. The second output, Rethinking governmentality: lessons from the academisation project in England, deploys and develops Foucaultâs theory of governmentality to generate new insights into the restructuring of the school system in England. The third output, Leaders and leadership in a climate of uncertainty: a case study of structural change in England, explores the involvement of three school leaders in local agenda setting and decision making, and their perceptions of that process. The fourth output, Admissions policies and risks to equity and educational inclusion in the context of school reform in England, reveals dilemmas relating to equity and educational inclusion. I conclude with a critical synthesis of the findings from the four outputs, in order to address my research questions; a summary of the contributions to knowledge; and recommendations for policy makers, professionals working in schools, and the research community. Taken as a whole, the thesis makes original contributions to knowledge in its claim that academisation should be viewed as a process of change, not of policy enactment; in its conceptualisation of the Academisation Policy Complex; in its evidence that a school can be âacademisedâ without becoming an academy; and in a data-generation schedule that was synchronous with the process under scrutiny. It also challenges, develops and advances thinking reported in previous scholarly writing, on governmentality, school leadership and the theorisation of change.