Mood shapes our behavior and interactions. We regulate our own mood, for example, by seeking support from others, while also attempting to influence the moods of those around us. In service settings, this regulation is crucial, as customer experience and satisfaction largely depend on frontline interactions where mood impacts perceptions of service quality. Service providers who can recognize and regulate their own mood, as well as identify and adapt to client moods, can enhance customer satisfaction while supporting their own well-being. Emotional Intelligence (EI) plays a key role in this process, equipping providers to manage these interactions effectively. Providers can be supported in skillfully managing both their own and clients' moods through designed products, targeted interventions, and training programs. However, while mood’s impact is well-recognized and some training efforts focus on self-regulation, empathy, and communication, research on how service providers manage client moods still requires investigation, and there is a lack of specific training for interpersonal mood regulation in service contexts.
This thesis investigates the role of mood and interpersonal mood regulation (IMR) within one-on-one service encounters, such as those between government employees and citizens or healthcare providers and patients. The study addresses four key questions: (1) understanding the role of mood in service encounters, (2) identifying IMR strategies used by service providers, (3) developing tools to support IMR strategies, and (4) evaluating the effectiveness of these tools.
Through an experience sampling study, the first chapter introduces a “Framework of Mood-Sensitive Interaction” highlighting service providers' ability to manage their own moods and those of clients. The framework’s four components—noticing own mood, regulating own mood, interpreting client's mood, and adjusting communication—provide a foundation for nine interpersonal mood regulation strategies: Understanding, Calming, Encouraging, Sociable, Efficient, Apologetic, Tolerating, Blunt, and Distant. To communicate these strategies, three tools are developed and validated: IMR strategy cards, videos, and character-based animations, each aiming to facilitate interpersonal mood regulation skills for service providers. Findings suggest these tools help service providers become aware of the strategies and help them to talk about them.
This work contributes to positive design and organizational psychology by providing practical tools and insights for training programs aimed at enhancing client-provider interactions and service-provider well-being. It offers foundations for future research and practice in designing for interpersonal mood regulation.

This article introduces the concept of mood sensitivity: a service agent's ability to detect mood during service encounters and customize their interaction style accordingly, with the purpose of improving service encounters as a whole. We report on an experience sampling study that explored the role that mood plays in service provision. Eleven service providers from various fields (education, healthcare, government) participated. The study yielded four general components of service encounter mood sensitivity. The first two represent “the eye outward”: (1) being perceptive of the client's mood and (2) being able to manage the client's mood by strategically adjusting one's interaction style. The other two represent “the eye inward”: (3) being perceptive of one's own mood and (4) being able to regulate one's mood to protect personal well-being and avoid negatively impacting an encounter. Our framework of mood sensitivity during service encounters integrates these four components. For each component, opportunities are proposed for the development of tools, training methods, and design interventions that can support service providers seeking to develop their mood sensitivity.

When having a conversation, we often adjust our communication style to respond to the mood of the other person: We talk differently to a person when they are cheerful than when they are grumpy (Niven, Totterdell & Holman, 2009). This ‘mood-sensitive communication’ is particularly important in the context of service encounters because the interaction with frontline service providers is a key determinant of customer experience and loyalty (Zomerdijk & Voss, 2010). A challenge in understanding and regulating such experiences is that they are difficult to distinguish because they are strongly intertwined in our daily interactions. To demonstrate the value of embodiedexperiences in the domain of experience research, we want to engage the audience in an actual experience by using a newly developed and validated card-based tool.