Scientific studies on sustainability are crucial for the promotion of resource conservation and environmental protection. They provide valuable insights for developing strategies to optimise reusable systems and reduce environmental impact. In cooperation with environmental and trade associations as well as reusable-oriented companies, the Stiftung Initiative Mehrweg (SIM) analyses specific key topics every year and integrates the results into the environmental policy dialogue. These studies provide important data for a more sustainable future and support the long-term stabilisation and increase of reusable packaging in all economic sectors.