PurposeThis study aims to explore factors that contribute to auditee satisfaction in external audit fieldwork of ISO 9001, and relationships between these factors.Design/methodology/approachThe purpose is addressed through a single case study and based upon data collected by a questionnaire. Data were analysed using probabilistic graphical models.FindingsAn auditor's knowledge of operations is shown to be the single most important factor contributing to auditee satisfaction in the study. Furthermore, establishing a co-operative audit atmosphere and focussing on business improvements support the co-creation of value in the interaction between auditor and auditee, while a focus on ISO compliance appears to be more of a hygiene factor.Research limitations/implicationsThis paper is based on a study of one company and its interactions with one of the certification bodies for external auditing. Hence, the generalisability of the findings is limited by the case study method.Practical implicationsThis paper identifies that an auditor's knowledge of operations and a focus on improvements and co-creation of value can improve auditee satisfaction and appreciation of the audit process.Originality/valuePrevious research has concluded that audit fieldwork is a key attribute associated with auditee satisfaction. This paper adds to this body of knowledge by empirically examining the specific factors within audit fieldwork that contribute to auditee satisfaction and focuses on value-creation in the audit process. By understanding these factors and moving towards a service perspective on audits with value co-creation as focus, it is possible to enhance the value of external audits.