This paper opens a new avenue for investigation of quality issues in servic
es. We take the viewpoint that a substantial portion of service failures is
the result of human error in the delivery process. Drawing upon the Generi
c Error Modeling System (GEMS) from the cognitive science literature, we de
velop a framework for understanding the role of human error in service fail
ures. An empirical investigation assesses the applicability of this framewo
rk to services, identifies which error mechanisms are important sources of
service failure, and clarifies how the different roles of customers and pro
viders affect the errors made by each.