Our mental life is characterized by a wide variety of attitudes. We admire, pity, or envy other people, we intend to act, and we desire certain things. Just as these attitudes can be appropriately directed, they can also be misdirected. Martin Luther King may warrant admiration, but a con artist does not. Some recent literature argues that there is a normative feature, fittingness, that governs which attitudes are properly directed towards which things. This dissertation considers the axiological, meta-ethical, and normative work that fittingness can do. Part 1 discusses the role of fittingness in a naturalist and realist meta-ethics. On my proposed naturalistic reduction, fittingness would be a sui generis correspondence relation between attitudes and entities. Other normative features, notably value, would be defined in terms of fittingness. This approach draws on Brentano’s analogy between fittingness and truth, insofar as truth is often considered to be a correspondence between propositions and states of affairs. I then show how my account can resist two kinds of error-theoretic arguments against normative realism. Part 2, on normative explanation, defends a fittingness-based account of recognition respect. Darwall (1977) famously identified recognition respect as a form of respect that is owed to something in virtue of its status as a certain kind of thing, rather than because of its excellence or success. For example, persons may warrant respect simply because of their status as autonomous agents. So understood, recognition respect has long been influential in non-consequentialist theory. But recognition respect is seldom defined in detail. I argue that fittingness is the normative feature best-suited for defining recognition respect. The definition I defend is largely a reduction of recognition respect to fittingness; to show recognition respect for x is to take the attitudes (conative, evaluative, or both) that it’s fitting to take to-wards x, because of one’s recognition that these attitudes are fitting. Given such a fit-based definition of recognition respect, we can better explain why respect-based normative theories count as non-consequentialist. Additionally, appeals to fittingness allow the non-consequentialist to explain normative facts about obligation and permissibility. Part 3, on axiology, defends a fittingness-based account of reasons. A key challenge is that while reasons are consequence-dependent and gradable, fittingness is typically considered to be both non-gradable and consequence-invariant. I review extant fit-based criteria that attempt to address this challenge. These criteria either yield unintuitive results or threat-en the role of fittingness in non-consequentialist explanation. In response, I defend novel fit-based accounts of both reasons and the weights of reasons. Together, these new criteria preserve the non-gradability and consequence-independence of fittingness, while explaining how reasons can be both gradable and consequence-dependent. As a result, given its meta-ethical, normative, and axiological roles, fittingness is a versatile feature that warrants a prominent place in our normative theorizing.