We summarize the three interlocking affect control theories (affect control theory (ACT), affect control theory of self (ACT-S), and affect control theory of institutions (ACT-I)), and recent studies that use the theories to illuminate issues of sociological interest. According to ACT, the micro-level theory, individuals create and perceive events in ways that maintain the relatively fixed affective meanings tied to social concepts in the events, with affective meanings operationalized with the dimensions of evaluation (good-bad), potency (powerful-weak), and activity (active-inactive). According to ACT-S, the individual-level theory, individuals seek feelings of authenticity by adopting and enacting identities with affective meanings similar to their self-meanings and by enacting identities that counterbalance affective disturbances from non-confirming events. According to ACT-I, the macro- and meso-level theory, individuals use organized actions within institutions to generate goods and services. Those organized actions contribute to a culture’s semantic system, which delineates the logical and functional relationships among the culture’s identities. Individuals’ knowledge of that semantic system creates an awareness of institutions, facilitates social interaction, and shapes the development of the self. Both ACT and ACT-S are cybernetic, mathematically based, and accessible through Interact, a computer program that simulates social interaction (ACT) and identity adoption (ACT-S) using the theories’ equations. Both also have a Bayesian version that uses probabilistic and decision-theoretic models. The three theories have been used to explain the emergence and persistence of inequalities of class, gender, race, sexuality, and health across several institutional domains.