While Weber’s distinction between ‘ideal’ and ‘material’ interests is one of the most enduring aspects of his theoretical legacy, it has been subjected to little critical commentary. In this article, we revisit the theoretical legacy of interest-based explanation in social theory, with an eye to clarifying Weber’s place in this tradition. We then reconsider extant critical commentary on the ideal/material interest distinction, noting the primarily Parsonian rendering of Weber and the unproductive allegiance to ‘generic need’ readings of Weber’s action theory. (...) We reconstruct the basis of the ideal/material interest distinction in the work of Rudolph von Ihering and provide a sounder basis for its analytic role in Weber’s ‘grand’ project. (shrink)