The European Commission published the “EU action plan for the Circular Economy” in 2015, the Dutch government strives for a circular Netherlands before the year 2050 (Rijksoverheid, 2016) and Rotterdam aims for circularity as the norm in 2030 (Rotterdam Circulair, 2018). To reach these goals, set by governmental organisations, change is required in all levels of society: individuals, municipalities, companies and other types of organisations. This master thesis focuses on the role of companies in the transition towards a circular economy. Companies often have limited insights in their circular performance. A current state analysis is needed to set realistic targets and keep track of the progress. Currently, there is a lack of workable tools that facilitate this analysis. For such a tool to contribute to the acceleration of the progress towards a circular economy, it is considered of great importance that it is easy in use and stimulates the user to action. This research developed a self-assessment rubric to create insights in the circular performance of an individual company. A case study was conducted for the Dutch plastics industry. The result was tested in cooperation with three companies and the results proved to generate relevant insights.