Abstract
Using market-based pro-poor development policy in the global South as an example, this paper engages with the rise of behaviourism and experimentalism as a challenge to the neoclassical orthodoxy and the more recent transformation into an influential policy script. After charting the rise of behavioural economics and discussing the key conceptual building blocks of the emerging behavioural mainstream in economics, the paper turns to the marketization of anti-poverty policy in the global South. Based on an analysis of policy documents, project reports and academic interventions, it is argued that the behavioural approach to poverty shifts the focus from the market to the market subject and engages in often thinly veiled attempts at behavioural engineering. This is achieved with the combined work of behavioural economic knowledge and socio-technical market devices.