The Sustainable Development Goals (SDGs) were adopted in 2015 by all UN member states and represent an ambitious, far-reaching programme of action. If implemented, they would set nations on a course that significantly enhances the prospects for sustaining human progress with a lower level of environmental impacts than today’s development pathway. The SDGs are the latest manifestation of a process than can be traced at least as far back as the Earth Summit in Rio de Janeiro in 1992. There, over 170 countries adopted Agenda 21, a comprehensive action plan to catalyse a global partnership for sustainable development aimed at improving human lives and protecting the environment. The Earth Summit was a significant milestone; it established the fundamental principle that the attainment of healthy and productive lives in harmony with nature should be at the heart of the sustainable development agenda. It led to a number of crucial international conventions including the UN Framework Convention on Climate Change and the UN Convention on Biological Diversity. Nevertheless, subsequent progress was disappointing in several respects. The creation of a fair and just trading system which would foster the development of least developed countries proceeded slowly, with many wealthy nations maintaining subsidies favouring their own interests. Growth in development assistance proceeded at a slower rate than agreed and inequities between and within nations were pervasive, offsetting many of the potential benefits of economic growth. Environmental degradation continued apace, as we have seen, and the opportunity to capitalize on the momentum of the Earth Summit largely dissipated (1).