Rigamonti, Lucia; Mancini, Eliana; Bellan, Martina

In a context where the transition to a circular economy is increasingly required, it is necessary to clarify the relationship between sustainability and circularity. Regarding the assessment of environmental sustainability, Life Cycle Assessment (LCA) methodology is fully accepted by the scientific community. Recently, circularity indicators have been introduced to provide information on the level of circularity about a given system or product. In this presentation we discuss the relationship between LCA and circularity indicators as well as their role in the improvement of circular decision making. After an analysis of recent studies that include both LCA evaluation and circularity assessment we can state that no authors have concluded that circularity indicators can be used alone to choose the best circular economy projects. Indeed, a circularity indicator only provides a partial view on the multiple environmental performance of a system. However, circularity indicators are easier to communicate than an LCA study, and a high degree of circularity could help to build good relationships with customers and increase reputation among stakeholders, as well as to have an easier access to funding. In conclusion, a study based on circularity indicators must be completed by an LCA study to verify that the circular system under study also leads to an improvement in environmental performance. Similarly, LCA studies that provide for innovations attributable to circular economy models can be completed with a circularity assessment. For this reason, we propose a framework for a comprehensive assessment of circular economy strategies, considering both the environmental sustainability and the degree of circularity. When different options are under decision, first, an assessment of these should be performed through an LCA. Secondly, after the exclusion of those strategies resulting with the worst impacts, a circularity analysis could be performed in support to the decision maker.