More than 40 nations are proposing to boost their 'bioeconomy' - the part of the economy based in biology and the biosciences. Around US$2 trillion of products in agriculture and forestry, food, bioenergy, biotechnology and green chemistry were exported worldwide in 2014, amounting to 13% of world trade, up from 10% in 2007. These sectors are central to at least half of the UN Sustainable Development Goals (SDGs), from food security to ensuring energy access and health. But conflicting national priorities make it hard to align bioeconomy policies to meet the SDGs on a global scale. Ecological sustainability is a prime concern in rich and industrializing countries; inclusive rural development and equitable sharing of resources is central in developing countries. Decisions made in one place may be felt elsewhere. A global bioeconomy must rebuild natural capital and improve the quality of life for a growing world population. It should balance managing common goods, such as air, water and soil, with the economic expectations of people. Three types of innovation will be needed: technological (such as systems to reduce emissions), organizational (changes in institutional behaviour) and social (such as job creation).