Aim: The aim of this study is to investigate how the CSRD directive is being adopted, particularly the double materiality requirement’s influence on sustainability reporting and internal processes of Swedish public transport companies.

Method: A qualitative research design was employed, using semi-structured interviews with sustainability professionals at three different regional public transport organisations. Thematic analysis was conducted was conducted using Stakeholder Theory, Institutional Isomorphism, and Implementation Theory to understand the organisational behaviour observed in response to regulatory pressures.

Results and conclusions: The empirical findings show that the CSRD implementation process involved a significant restructuring of sustainability practices. This required companies to formalise new internal procedures, engage stakeholders in a more systematic way, and improve data collection across their complex value chains. The challenges they faced included a lack of initial guidance and limited data availability. Nevertheless, the CSRD process encouraged internal capacity building and fostered cross-departmental collaboration. Companies demonstrated varying levels of progress, often cycling through different stages of implementation.

Contribution of the thesis: This study contributes a new perspective by illustratinghow institutional pressures interact with implementation stages in a public-sectorcontext.

Suggestions for future research: Future researchers could explore the CSRD process over a longer time frame or conduct a similar study in other EU countries.

Key words: CSRD, double materiality, sustainability reporting, public transport,implementation theory, institutional isomorphism, stakeholder engagement.