This chapter focuses on the role of emotions in designing artifacts for mindful social interaction in the context of design as an agent for behavior change. The concept of mindfulness in design, also termed mindful design, refers to the attentiveness of the user toward the consequences of their actions performed with an object. An object which may specifically induce mindfulness of the social consequences of the user's actions is termed a performative object. Mindfulness can aid behavior change because it encourages reconsidering our actions and their causes, helping to adjust them to new situations. Using functional analysis, the research investigated the role of emotions in social interaction in relation to mindful choice. Existing and hypothetical situations and design examples are used to support the analysis. The research establishes a mindful–emotional framework, which provides robust guidance for the analysis of social situations/environments, and to facilitate designing performative objects for these situations. The benefit of the research is a better understanding of the design of performative objects and their application, and of their potential to contribute to behavior change.