Emotions are an important yet largely neglected aspect of scientific work. Little is known about their role in the constitution and maintenance of disciplines and disciplinary identities in spite of the earlier work of Fleck (1935) and Collins (1998). We present a theoretical account of disciplinary emotions and highlight their role in interdisciplinary interaction, focusing on scientific imperialism. We argue that disciplines are institutions with epistemic and organizational aspects that come together in internalized and enacted disciplinary cultures and identities that provide the intentional and psychological background for the emergence of disciplinary emotions. These are felt in the social identity of a scholar for reasons that relate to the epistemic or organizational aspects of the discipline. In interdisciplinary interaction, disciplinary emotions – such as feelings of superiority and inferiority, confidence and pride, envy and jealousy, or anger and fear – motivate proponents and opponents of scientific imperialism alike. We propose that imperialistic disciplines such as economics and evolutionary biology motivate their actions by second-order judgments about the interdisciplinary applicability of their first-order theoretical and methodological principles. Finally, we suggest that the justification of disciplinary emotions in the context of scientific imperialism should be evaluated in terms of their adaptiveness in promoting some epistemically desirable pursuits in scientific research.Peer reviewe