Summary: This Colloquium was organized to shed light on how the world will feed its still expanding population in a sustainable way while maintaining enough wildlands to support and preserve essential ecosystems services and biodiversity. The magnitude and activities of the human population make the task more complex than ever and more critical. The Colloquium brought together economists, demographers and other social scientists, as well as agronomists, biotechnologists, geneticists, and ecologists. The four scientific sessions focused on: demographic and economic projections of food demand and supply; limits on land, water, energy, and biological resources in agriculture; plant biotechnology; and biodiversity and multiple land use demands. Dominated by representatives of a single discipline, each session produced a markedly different vision of our planetary future.