Governments around the world have increasingly adopted behavioural public policies, in which behavioural insights units (often designated as ‘Nudge units’) play an increasingly important role. Such units are typically assigned with implementing behavioural insights in various social policy fields. However, research on the contextual specificities of Nudge units is still scarce. This article addresses that gap by providing an in-depth qualitative study of MineduLAB, a Nudge unit active within the Peruvian Ministry of Education. Informed by an interpretive approach, our analysis shows that the behavioural insights that MineduLAB makes use of and develops, are enacted by a unique local interplay of three different dimensions: a political-financial, an epistemic community, and a sector-specific (here: educational) dimension. Moreover, our analysis of a Nudge unit in the Global South showcases both similarities (e.g. focus on behavioural evidence and experimentation) as well as differences (e.g. the challenge of corruption; the deployment of other vocabulary with regards to behavioural insights) with the predominantly Western Nudge units that are more commonly researched. Consequently, we argue that for a profound academic evaluation of behavioural public policy and the role of Nudge units herein, it is crucial to pay close attention to their contextuality and geographical diversity.