Karl-Henrik Robert (b.1947) is a Swedish cancer scientist and founder of The Natural Step in 1989, a non-profit with offices in 12 countries and associates in >50 countries. TNS led to creating the Natural Step Framework, also known as the Framework for Strategic Sustainable Development (FSSN), setting system conditions for sustainability and guidelines for compliance with these principles. The four system principles/conditions are the elimination of increasing concentrations of i) substances extracted from the earth’s crust; ii) substances produced by society; iii) degradation by physical means, and iv) an end to undermining people’s capacity to meet their needs. Robert also founded Physicians for the Environment in 1991, committed to the health and environmental aspects of climate change, drugs, lifestyle issues, and chemicals. He has authored or co-authored numerous publications, including The Natural Step Story: Seeding a Quiet Revolution (2008) and The Sustainability Handbook (2012). Among various honors, Robert was awarded the Green Cross Award for International Leadership (1999), included in 100 Visionaries of the 20th Century by the Global Center for Leadership and Business, and received their Social Responsibility Laureate Medal (2005); also the Blue Planet Prize (2000) and Ashoka Globalizer (2011).