This report explores whether there are limits to robustness of a socio-economic system as the result of a linear metabolic structure, and how those limits could theoretically be affected by its transition to a circular economy. 

First, it looks at how the economic openness of the EU27 would affect the value of its circularity rate theoretically. Then it develops a conceptual framework based on regenerative economics and indicators from ascendency analysis and ecological network analysis. 

This framework is used to assess a theoretical future case where the EU27 manages to successfully transition to a CE within its given linear material flow metabolism. 

The results show that there are limits to robustness, and which do not necessarily correspond to a maximum circularity rate.