Purpose: The purpose of this paper is to examine how principals, deputy principals, heads of departments (HoDs) and teachers as leaders exercise their agency within and through the organisational structure of their schools to improve academic quality. Design/methodology/approach: A case study was conducted in the wider context of school-based leadership. Principals, deputy principals, HoDs and teachers selected by means of purposive sampling from six primary and secondary schools in Harare Province of Zimbabwe participated in the study. Findings: Leaders in schools in Harare Province were found to have the capacity to use their agency within and through the organisational structure to improve pass rates. They were able to use their agency to work within the supposed rigid bureaucratic organisational structures to enable bureaucratic organisational structures, or, in participants' views, democratic structures. Research limitations/implications: Some limitations of the research ought to be considered. The research scope and site had its limitations. The research site was limited to a few primary and secondary schools in Harare Province (one out of ten provinces) of Zimbabwe. Although the sampling procedures were implemented to ensure good representation of participants' views, the sampling was limited to a few schools. Owing to time and financial constraints, a larger sample could not be selected to conduct the interviews. These limitations are acknowledged, but they do not undervalue the significance of the study, as they can provide potential avenues for further research. For example, the study may be replicated in rural provinces of Zimbabwe. Such further research could help improve school leadership in Zimbabwe. Practical implications: Principals, deputy principals, HoDs and teachers as leaders can exercise their agency in the structure of their schools to improve academic quality, expressed as and measured by pass rates. School leaders who have a positive attitude and requisite experience are able to change the rigid bureaucratic structures of their schools to enable bureaucratic structures, which are similar to democratic structures. Originality/value: This paper provides a critical perspective on how leaders exercise their agency in the context of the organisational structure of their schools to improve academic quality.