Transforming the resource intensive construction sector is vital for the transition to circular economy. Incorporating changes to transition from linear to a circular way of working place significant demands on client organisations. The primary objective of our study is to develop a conceptual change model that provides recommendations on what internal changes can be implemented within public clients, to accelerate their transition to circular practises in infrastructure projects. A literature review indicates that models incorporating both process and content aspects are most effective in addressing comprehensive organisational change. Empirical data was gathered through case studies among public clients, being Dutch regional water authorities. The initial organisational change framework was validated and refined through expert interviews. The developed change model serves as a guiding tool for facilitating public clients' transition from their current state to the desired state through structured and achievable steps. The framework identifies four key areas of change: people, work process, structure, and external. For each of these four aspects, change measures are presented in the unfreeze-transition-refreeze steps, adopted from Lewin's change model for planned organisational change.