Nabila As'ad

Abstract
Purpose Dyadic interactions between customers and service providers rarely occur in isolation. Still, there is a lack of systematic knowledge about the roles that different types of nontechnological third parties - that is, other customers, pets, other employees and other firms - can adopt in relation to customers and service providers during encounters. The present study aims to unravel these roles and highlight their implications for customers, service providers and/or third parties. Design/methodology/approach This research relies on a systematic review of literature in the Web of Science using a search string pertaining to the research study's objectives. In total, 2,726 articles were screened by title and abstract using clear inclusion and exclusion criteria, thereby extracting 189 articles for full-text eligibility. The final sample consisted of 139 articles for coding and analysis. Findings The analyses reveal that other customers, pets, other employees and other firms can adopt five roles: bystander, connector, endorser, balancer and partner. Each role has different implications for customers, service providers and/or third parties. Additionally, the five roles are associated with distinct constellations of the customer, the service provider and the third party. These roles and constellations are dynamic and not mutually exclusive. Originality/value This research contributes to the service encounter literature by providing a thorough understanding of the various third-party roles and their implications for customers, service providers and/or third parties during encounters. As such, this research sheds light on the conditions under which third parties become "significant others" in service encounters and identifies avenues for future research.