Due to the traditional conceptualisation of delusion as ‘irrational belief’, cognitive models of delusions largely focus on impairments to domain-general reasoning. Nevertheless, current rationality-impairment models do not account for the fact that i) equivalently irrational beliefs can be induced through adaptive social cognitive processes, reflecting social integration rather than impairment; ii) delusions are overwhelmingly socially-themed; iii) delusions show a reduced sensitivity to social context, both in terms of how they are shaped and how they are communicated. Consequently, we argue that models of delusions need to include alteration to coalitional cognition – processes involved in affiliation, group perception, and the strategic management of relationships. This approach has the advantage of better accounting for both content (social themes) and form (fixity) of delusion. It is also supported by the established role of mesolimbic dopamine in both delusions and social organisation, and the ongoing reconceptualisation of belief as serving a social organisational function.