Emotion, and its expression, is present in almost every facet of life: in our personal relationships, morality, politics, and art. Over time, emotions have evolved and have become intimately connected to our bodies, as matters of existential and scientific importance. In a Sentimental Mood is a philosophical examination of what emotion is, the kinds of emotions there are, and the ways in which they are expressed in our behavior and other social and moral expressions.Jay Odenbaugh's goal is to integrate the diverse work in psychology, neuroscience, evolutionary biology, and behavioural ecology with that from the philosophy of biology and psychology. This integration provides a unified, naturalistic understanding of this key component of human experience. Odenbaugh argues that emotion is a multimodal perceptual experience integrating exteroception and interoception. They are seamlessly about our environment, ourselves, and more specifically how we are faring in that environment. Many are natural kinds in virtue of being causally structured clusters of elicitors, behaviours, and autonomic nervous activities. Emotions are culturally widespread even with local inflections of place. Finally, Odenbaugh fruitfully integrates the nature of moral judgments with the resources of teleosemantics and hybrid expressivism. These judgments both describe and direct us to reciprocate, aid, and punish. Covering a wide range of research on human evolution and culture and bringing them into conversation, In a Sentimental Mood provides a bold new account of human emotional experience while also providing a useful synthesis of the state of the art on the topic.