The autonomy of agencies often seems to trigger reregulation of those agencies. Reregulation has two dimensions: the layering of different control mechanisms and the growth of the rules within those layers. Using a case study of social housing in Belgium, we explain the tendency to reregulate once autonomy is provided. We attribute the layering of rules to a conflict regarding oversight between the established legal profession and an ascending management profession. Crozier’s vicious circle of bureaucratization helps to explain the growth of regulation within layers. The legal culture of the Rechtsstaat is a catalyst for both professional competition and bureaucratization.