Corporatization reforms in the public sector are now a global phenomenon, although research highlights the gap between rhetoric and reality. While corporatisation offers to increase the formal autonomy of public organisations and their managers, in practice greater autonomy is often not realised. However, our comparative understanding of these reforms and the role of national, institutional and cultural conditions remains under-developed. In this paper we address this concern focusing on the mediating role of clientelism and patronage. As an empirical case we focus on the experience of corporatisation in the Iranian healthcare sector where management relationships are heavily influenced by patronage networks. Our analysis of two public hospitals highlights the contrasting way patronage networks shape the degree of autonomy experienced by managers. While in one hospital the patronage system facilitated autonomy, in the other managers felt less empowered. We conclude by arguing that more attention should be given to the role of patronage and clientelism in understanding the nature and impact of NPM reforms, especially in developing country contexts.