René Estermann is a Swiss pioneer in sustainability. Shortly after completing his secondary education, he built his first municipal composting facility. While studying agricultural economics at ETH Zurich, he founded the engineering and consulting company Composto+ in 1990, which played a key role in developing organic waste management in Switzerland and abroad. From 2006 to 2018, he served as CEO of the myclimate foundation, transforming it into a leading international climate organisation with offices in ten countries. Following his role as Director at South Pole (2019–2020), he has headed the City of Zurich’s Office for Environmental and Public Health Protection since 2020, where he is responsible for shaping and implementing the city’s environmental strategy.