This article presents an affect theory of social exchange, which argues that emotions generated by social exchange processes are critical to understanding how and when social exchanges promote or inhibit solidarity in relations or groups. The theory emphasizes that emotions are internal reinforcements or punishments that influence how actors perceive and feel about their shared activity, their relations, and/or their common group affiliations. It expands the domain of exchange theorizing by incorporating emotions as a central feature of social exchange processes. The theory conceptualizes social exchange as a joint activity where each actor has something the other values. The implicit or explicit task is to generate benefit for each individual by exchanging behaviors or goods that actors cannot achieve alone. The affect theory of social exchange expands the domain of exchange theorizing in two main ways: (1) exchange outcomes—rewards and punishments—are construed as having emotional effects that vary in form and intensity, and (2) social exchange is a quintessential joint activity, but the nature and degree of jointness varies. The theory argues that emotions produced by exchange structures and processes are critical to understanding how and when social exchanges promote or inhibit solidarity in relations or groups. It moves beyond the traditional Skinnerian foundation of exchange theory and its more recent rational choice variants. The theory also complements other approaches by analyzing how actors experience, interpret, and respond to their own emotions and feelings produced by successful or unsuccessful exchange efforts. The theory proposes that emotions are integral to the normative context of exchange and often managed carefully by actors. Emotions are subtle signals to actors about their own responses in interaction and provide information on the intentions or orientation of others. The affect theory of social exchange focuses on the emotional/affective process in order to broaden and deepen theorizing of the emotional effects of exchange. The theory poses two interrelated questions: (1) Under what structural conditions will exchange produce emotions and feelings? (2) Under what conditions will this emotion be attributed to social units (relations, groups, organizations) and, therefore, generate collectively oriented behavior? The core idea of the proposed theory is that structural interdependencies among actors produce joint activities that, in turn, generate positive or negative emotions; these emotions are attributed to social units under certain conditions, thereby producing stronger or weaker individual-to-collective ties. The theory also discusses the implications of different exchange structures on these conditions and on cohesion and solidarity. It argues that emotions produced by exchange structures and processes are critical to understanding how and when social exchanges promote or inhibit solidarity in relations or groups. The theory also discusses the differences between various forms of exchange structures, such as productive, negotiated, reciprocal, and generalized exchange, and their effects on emotions and shared responsibility. The theory concludes that productive exchange produces the strongest global feelings and perceptions of shared responsibility, followed by direct exchange, and then indirect exchange.This article presents an affect theory of social exchange, which argues that emotions generated by social exchange processes are critical to understanding how and when social exchanges promote or inhibit solidarity in relations or groups. The theory emphasizes that emotions are internal reinforcements or punishments that influence how actors perceive and feel about their shared activity, their relations, and/or their common group affiliations. It expands the domain of exchange theorizing by incorporating emotions as a central feature of social exchange processes. The theory conceptualizes social exchange as a joint activity where each actor has something the other values. The implicit or explicit task is to generate benefit for each individual by exchanging behaviors or goods that actors cannot achieve alone. The affect theory of social exchange expands the domain of exchange theorizing in two main ways: (1) exchange outcomes—rewards and punishments—are construed as having emotional effects that vary in form and intensity, and (2) social exchange is a quintessential joint activity, but the nature and degree of jointness varies. The theory argues that emotions produced by exchange structures and processes are critical to understanding how and when social exchanges promote or inhibit solidarity in relations or groups. It moves beyond the traditional Skinnerian foundation of exchange theory and its more recent rational choice variants. The theory also complements other approaches by analyzing how actors experience, interpret, and respond to their own emotions and feelings produced by successful or unsuccessful exchange efforts. The theory proposes that emotions are integral to the normative context of exchange and often managed carefully by actors. Emotions are subtle signals to actors about their own responses in interaction and provide information on the intentions or orientation of others. The affect theory of social exchange focuses on the emotional/affective process in order to broaden and deepen theorizing of the emotional effects of exchange. The theory poses two interrelated questions: (1) Under what structural conditions will exchange produce emotions and feelings? (2) Under what conditions will this emotion be attributed to social units (relations, groups, organizations) and, therefore, generate collectively oriented behavior? The core idea of the proposed theory is that structural interdependencies among actors produce joint activities that, in turn, generate positive or negative emotions; these emotions are attributed to social units under certain conditions, thereby producing stronger or weaker individual-to-collective ties. The theory also discusses the implications of different exchange structures on these conditions and on cohesion and solidarity. It argues that emotions produced by exchange structures and processes are critical to understanding how and when social exchanges promote or inhibit solidarity in relations or groups. The theory also discusses the differences between various forms of exchange structures, such as productive, negotiated, reciprocal, and generalized exchange, and their effects on emotions and shared responsibility. The theory concludes that productive exchange produces the strongest global feelings and perceptions of shared responsibility, followed by direct exchange, and then indirect exchange.