Research-Thesis: Directive 2022/2464 (CSRD): enjeux et défis de la vérification des informations ESG par les auditeurs externes - illustration à travers la thématique de la biodiversité et des écosystèmes.

Abstract

This research examines how external auditors perceive the challenges associated with the verification of ESG information under the CSRD framework, and how biodiversity and ecosystems shed light on the ongoing transformation of audit practices. The study is based on 11 semi-structured interviews conducted in Belgium with a mix of financial and ESG auditors, ESG experts and institutional representatives, from both Big 4 and non-Big 4 firms. The findings show that auditors currently approach ESG assurance through an increased reliance on professional judgment, the use of complementary expertise and the gradual adaptation of audit practices within a still evolving framework. These results highlight the emerging nature of ESG auditing, where the complexity of double materiality is driven not only by technical challenges, but also by the absence of well-established standards and heterogeneous interpretative practices. In this context, professional judgment plays a central role as an adaptive mechanism for managing structural uncertainty rather than as a mere extension of financial audit practices. The study further reveals that ESG auditing is becoming increasingly hybrid, relying on interactions between auditors, experts and technological tools. Required competencies are therefore distributed rather than concentrated in a single profile, combining audit expertise, technical knowledge and adaptability. However, the role of technology remains largely supportive, as its integration is constrained by the limited standardization and heterogeneous nature of ESG data, which restricts the potential for automation. Finally, the analysis of biodiversity and ecosystems illustrates the most pronounced limitations of current ESG audit practices. This area highlights a form of complexity that is not only technical, but also cognitive and institutional, stemming from the limited maturity of practices, auditors’ lack of experience, and the absence of stabilized methodological frameworks. It thus underscores the broader difficulty of establishing robust audit approaches in still emerging areas.