Discussion of “Generalized Trust and Nonaudit Services” by Guo, Hartlieb, and Niemi (2026)

Guo et al. ( 2026 ) investigated whether country-level generalized trust is associated with the provision of auditor-provided nonaudit services (NAS) in Europe. Using a large cross-country sample covering 2011–2020, the authors documented a positive association between societal trust and both the level and proportion of NAS. They presented additional analyses addressing capital market perceptions, regulatory quality, NAS restrictions, and different NAS categories. In this discussion, I review the paper’s contributions by emphasizing its key strengths, including the importance of trust in the auditing setting, its treatment of trust as an informal institutional determinant of audit market outcomes, and the use of a multicountry European setting. At the same time, I raise selected conceptual, institutional, and methodological considerations. In particular, the discussion examines the applicability of generalized trust in audit settings, the credibility of competing theoretical mechanisms, the role of regulation and selection in shaping observed NAS outcomes, and limitations related to the measurement of trust.