“…The present study has as main goal, the analysis of service data and complaints from external customers of a telephone company, investigating service failures, discovering factors that affect the complaint counts and proposing suggestions for improvements, especially in the technical service area. Studies on customer complaints are of great interest in companies in different sectors (Anderson, Fornell & Mazvancheryl, 2004;Claro et al, 2014;Coelho et al, 2016;Fornell & Wernerfelt, 1987;Luo, 2007Luo, , 2009Romani, Grappi & Dalli, 2012;Singh & Wilkes, 1996;Singh, 1988). The research developed in a telecommunications company, which operates in the central region of the São Paulo state.…”