Ambulance service personnel experience an array of emotions when working on shift. Nevertheless, there has been a lack of research to date regarding the interpersonal effects that frontline staff members’ emotional experiences and displays can have on their crewmates’ behavior and emotional state. This study used a critical realist research approach to explore the influential within-dyad effect of emotional exhibitions in frontline ambulance pairs. Ambulance service personnel (N = 18) were recruited to take part in individual interviews and to complete postshift voice diaries. Using abductive analysis methods, evidence for the emotions as social information (EASI) model processes, affective reactions and inferential processes, was presented through examples of self-reported interpersonal emotional transfer and emotional regulation. In addition, retroductive analysis of the interview and voice diary transcripts identified facilitative factors affecting the enaction of these social–emotional processes. The themes of understanding each other, managing emotions differently, expectations from above, and responding to different callouts were reported to contribute to the tendency for affective reactions and inferential processes to occur. These findings provide support for the impact that EASI model concepts can have in performance domains and offer evidence to suggest how these socially influential processes may be contextually facilitated. The results presented in this study can be used by ambulance service trusts to better understand and improve the emotional relationships of their frontline dyads.