Roughly, the noetic account characterises scientific progress in terms of increased understanding. This chapter outlines a version of the noetic account according to which scienti?c progress on some phenomenon consists in making scienti?c information publicly available so as to enable relevant members of society to increase their understanding of that phenomenon. This version of the noetic account is briefly compared with four rival accounts of scientific progress, namely the truthlikeness account, the problem-solving account, the new functional account, and the epistemic account. In addition, the chapter seeks to precisify the question that accounts of scientific progress are (or should be) aiming to answer, namely ‘What type of cognitive change with respect to a given topic or phenomenon X constitutes a (greater or lesser degree of) scientific improvement with respect to X?’