This paper explores the link between the case for indeterminism in an epistemological fashion and methodological individualism in the thought of two defenders of both stances: Karl Popper and Friedrich Hayek. The relation between these issues has not received much attention before and even less so with regard to these two thinkers. First, Popper’s defence of indeterminism from an epistemic viewpoint and Hayek’s views about the indeterminism of action are studied. Second, their positions about methodological individualism are considered. Finally, several (...) comparative questions are aired. (shrink)