Expressive Order introduces affect control theory to lay readers of sociology, and additionally guides sociology specialists into the theory's deep structure. Briefly, affect control theory proposes that individuals shape their social interactions so that emerging impressions reinforce sentiments about salient identities, behaviors, and settings. Emotions signal how the process of confirming sentiments is going for each individual. The theory explains behaviors, emotions, social labeling, and personality attributions in a wide variety of social contexts – including intimate relations, work-world interactions, courtrooms, and international relations. Part 1 of the book provides a plain-language exposition of the theory, along with numerous interpretive analyses of everyday situations. This is engaging and provocative reading for anyone interested in social relations, including undergraduates in and out of the social sciences. Part 2 presents the mathematical derivations that define sentiment-confirming behavior, labeling, attribution, and emotion. The mathematical solutions, conjoined with understandings about social institutions, are the basis of the theory's explanations. The derivations clarify the theory's assumptions and reasoning, as only mathematics can. Part 3 of Expressive Order describes the research program associated with the theory and the computer simulation software that is used in research. This part of the book offers a jump start for individuals wishing to use affect control theory in their own research.