Stiftungsfonds für Umweltökonomie und Nachhaltigkeit GmbH (Foundation for Environmental Economics and Sustainability), or SUN, was established in September 2014 by the Deutsche Post Foundation in Bonn, Germany. SUN supports institutions, programmes, and projects dealing with the challenges and opportunities of environmental protection and sustainable development.

As a Philanthropic Partner, SUN enables the Ellen MacArthur Foundation to explore new areas of research and insight that will help accelerate the global transition to a circular economy.

The partnership follows a previous successful collaboration between the two organisations, with SUN sponsoring the influential 2015 report Growth Within: a Circular Economy Vision for a Competitive Europe authored by the Ellen MacArthur Foundation and the McKinsey Center for Business and Environment. The report was presented at the European Commission’s stakeholder conference on the circular economy in Brussels, which led to the adoption of the EC Action Plan for the Circular Economy in December, opening up EUR 24 billion of existing finance to circular economy businesses.