The paper considers what can be done to develop equitable education systems by describing and analyzing a three-year initiative that took place across a city in Scotland. Set in a particularly challenging context, with high levels of socio-economic disadvantage, the study involved a design-based implementation research methodology within which findings from earlier research were adapted to suit the particular context. This led to an emphasis on collaborative action research within schools and across partnerships of schools to support the process of change. All of this was coordinated by a strategy group mainly made up of experienced headteachers who took on the role of system leaders. Based on the evidence that was generated, the paper goes on to suggest propositions that may be relevant to those concerned with addressing this agenda in other contexts. This analysis throws light on the barriers that were experienced in putting this thinking into practice. Consideration is also given to the roles of research and researchers within such developments.