Purpose The purpose of the thesis is to contribute toward establishing the relationship between the concepts of sustainability reporting, sustainability performance, and sustainability reputation.This will be done by investigating the causal relationships between these concepts and whether those relationships are negative or positive. Methodology The study is based on a positivistic philosophy with a deductive approach. By using a quantitative method and a longitudinal design, the causal influences from the independent variables in 2019 to the dependent variables in 2020 could be investigated in a sample of 99 companies. This was done by 297 firm-year observations for measuring sustainability performance, and by 198 firm-year observations for measuring sustainability reputation and sustainability reporting respectively. Secondary data from the agency SB Insight together with primary data from companies’ sustainability reports and annual reports were mainly tested by a multiple linear regression model. Findings The findings show that sustainability reporting is negatively affected by sustainability performance and indicate that the causality is unilateral from sustainability performance tosustainability reporting. Sustainability reputation is positively affected by sustainability reporting, but sustainability reporting is in addition positively affected by sustainability reputation, indicating a bidirectional relationship where the causality remains unsolved. The findings show no significant association between sustainability performance and sustainability reputation. Furthermore, the thesis suggests a new concept to the research field, namely the reporting-reputation-spiral. Theoretical Perspectives The study analyzed the results through the legitimacy theory, the stakeholder theory, the voluntary disclosure theory, and the signal theory