In the course of sustainability becoming an increasingly relevant topic in society, especially the concept of circular economy gained traction in organisational practice. However, a multitude of varying approaches blur the theoretical principles of the concept and the appropriateness of its practice. How organisations counteract this legitimacy issue by means of narratives is the subject of this thesis project. Aiming at the provision of new insights on this matter, a qualitative research approach in form of a multiple case study was applied. The cases involve four Swedish organisations from different business sectors (information technology/E-commerce/waste management/furniture). They provided narratives about circular economy and their corresponding practices through their websites and interviews. The findings illustrate that each organisation communicates about circular economy but to different extents, through diverse channels, and with varying definitional foci. In summary, seven legitimation strategies were identified in the organisational narratives: authorising the underlying definition of circular economy, demonstrating consistency between definition and practice, aligning the narratives with the public’s mental models, projecting legitimacy of other actors onto the organisation, evoking emotions, spreading the concept to build institutions, and admitting imperfection of practices.