This chapter aims to shed light on the relation between Hesse’s mature work—the culmination of which is arguably her 1974 book The Structure of Scientific Inference and the theoretical perspective that Feyerabend elaborated roughly from 1958 to 1970. The goal is not to present a philological inquiry into the extent to which Hesse’s work can be traced back to Feyerabend. Instead, the aim is to better understand the extent to which the content of Hesse’s general philosophy of science is determined by the issues, topics, and sensibilities that belong to the post-Popperian tradition in epistemology. To achieve this, this chapter will detail Hesse’s engagement with and further development of several concepts and stances that characterized Feyerabend’s philosophy before the publication of Against Method. This analysis will shed light on where Hesse situates herself within the post-Popperian milieu, her series of arguments directed against positivist philosophy of science, and the way in which her position overcomes specific issues and difficulties that undermine Feyerabend’s position. This will provide us with a better appreciation of both thinkers’ approaches to themes such as theory change, explanation, and the theory-ladenness of observational terms. The conclusion will briefly consider whether a more continued interaction of Hesse’s epistemology with Feyerabend’s stance might have benefited her later work.