The diversity of knowledge surrounding behavioural insights (BI) means in the policy sciences, although visible, remains under-theorized with scant comparative and generalizable explorations of the procedural prerequisites for their effective design, both as stand-alone tools and as part of dedicated policy 'toolkits'. While comparative analyses of the content of BI tools has proliferated, the knowledge gap about the procedural needs of BI policy design is growing recognizably, as the range of BI responses grows in practice necessitating specific capabilities, processes and institutional frameworks to be in place for their design. This Element draws on the literature on policy design and innovation adoption to explore the administrative, institutional and capacity endowments of governments for the successful and appropriate integration of BI in existing policy frameworks. Further, we present three illustrative cases with respect to their experience of essential procedural endowments facilitating for the effective integration of BI in policy design.