Negative emotions are often thought to lack value—they’re pernicious, inherently unpleasant, and inconsistent with human virtue. Taking anxiety as a case study, this chapter argues that this assessment is mistaken. It starts with an account of what anxiety is: a response to uncertainty about a possible threat or challenge that brings thoughts about one’s predicament (‘I’m worried,’ ‘What should I do?’), negatively valenced feelings of concern, and a motivational tendency toward caution regarding the potential threat one faces. Given this account of what anxiety is, it is argued that anxiety can be instrumentally valuable: in sensitizing us to uncertainty and prompting caution and risk assessment efforts, it’s an emotion that can help us better recognize and respond to uncertain threats and challenges. But anxiety can also be aretaically valuable—that is, it’s an emotion that can contribute positively to one’s character. For instance, your anxiety about how best to care for your aging mother not only prompts helpful brainstorming about what you should do, but also reflects well on you—your unease demonstrates both an admirable sensitivity and emotional attunement to what’s at stake.