Influential Factors and Key Actors Shaping Sustainability Assurance Opinions: A Case Study of a Big-4 Firm

Sammanfattning: The rise in sustainability reporting has increased the demand for sustainability assurance, especially in the light of new legislation, requiring more companies to undergo third-party assurance. This thesis provides insights into the practical work of a sustainability assuror in the sustainability assurance process and how sustainability assurance opinions are formed as well as how materiality is constructed. To provide these insights, we have conducted a single case study in a Big-4 firm located in Sweden. We have used theories and methodologies from Pentland (1993) to construct our theoretical framework in a similar matter as Catasús & Carrington (2007). Our findings show that production and transfer of comfort affect the formation of sustainability assurance opinion and that the sacred signature is the most important element in the production and transfer of comfort for external stakeholders. Our findings also show that FAR's sustainability specialist group functions as a social control mechanism through FAR as an institution that contributes to creating industry standards within the sustainability assurance industry.