 It is primarily this combination of evaluation and non-evaluative description that has attracted philosophical attention to thick concepts in ethics since the mid-twentieth century. Thick concepts have been thought to provide leverage in various debates concerning the nature of evaluative thought and talk and to illuminate such questions as whether there is a robust fact-value distinction, whether ethical claims enjoy a significant kind of objectivity, and how evaluative classifications relate to non-evaluative classifications. Doing justice to the full diversity and complexity of moral thinking has also been thought to require more attention to thick concepts. The focus on thin concepts over the thick in much of the history of Western moral philosophy threatens to simplify and mislead also in normative ethics, where the revival of virtue ethics as a major alternative to deontology and consequentialism coincides with increased attention to thick terms and concepts in metaethics. Interest in thick concepts has also extended from ethics to other areas of philosophy such as epistemology and aesthetics. Several questions run through all these motivations for focusing on thick concepts. We have a “combination question”: how exactly do thick terms and concepts combine evaluation and non-evaluative description? We have a “location question”: is evaluation somehow inherent to thick terms and concepts, such as perhaps an aspect of their meaning, or merely a feature of their use? We have a “delineation question”: how do thick terms differ from the thin and from other kinds of evaluative terms (such as pejorative expressions)? Given answers to these questions, what broader significance within ethics and applications outside of ethics might thick ethical concepts have? What follows is a survey of various attempts to answer these questions.