Introduction Bjorn Lomborg; Part I. The Solutions: 1. Armed conflicts J. Paul Dunne; 1.1 Alternative perspective Anke Hoeffler; 1.2 Alternative perspective Andrew Mack; 2. The challenge of ecosystems and biodiversity Salman Hussain, Anil Markandya, Luke Brander, Alistair McVittie, Rudolf de Groot, Olivier Vardakoulias, Alfred Wagtendonk and Peter H. Verburg; 2.1 Alternative perspective Juha V. Siikamaki; 2.2 Alternative perspective John C. Whitehead and Paul E. Chambers; 3. Chronic disease prevention and control Prabhat Jha, Rachel Nugent, Stephane Verguet, David Bloom and Ryan Hum; 3.1 Alternative perspective Julia Fox-Rushby; 3.2 Alternative perspective Marc Suhrcke; 4. Climate change: CO2 abatement Richard S. J. Tol; Technology-led mitigation Isabel Galiana and Christopher Green; Climate-engineering R&D J. Eric Bickel and Lee Lane; Climate-change adaptation Francesco Bosello, Carlo Carraro and Enrica De Cian; 4.1 Alternative perspective Samuel Fankhauser; 4.2 Alternative perspective Anil Markandya; 5. Education: the case for improving school quality and student health as a development strategy Peter F. Orazem; 5.1. Alternative perspective Lant Pritchett; 5.2 Alternative perspective George Psacharopoulos; 6. Hunger and malnutrition: investments to reduce hunger and undernutrition John Hoddinott, Mark Rosegrant and Maximo Torero; 6.1 Alternative perspective Anil B. Deolalikar; 6.2 Alternative perspective Beatrice Lorge Rogers; 7. Infectious disease, injury, and reproductive health Dean T. Jamison, Prabhat Jha, Ramanan Laxminarayan and Toby Ord; 7.1 Alternative perspective Till Barnighausen, David Bloom and Salal Humair; 7.2 Alternative perspective David Canning; 8. Policy options for reducing losses from natural disasters: allocating $75 billion Howard Kunreuther and Erwann Michel-Kerjan; 8.1 Alternative perspective Stephane Hallegatte; 8.2 Alternative perspective Ilan Noy; 9. Population growth Hans-Peter Kohler; 9.1 Alternative perspective Oded Galor; 9.2 Alternative perspective David Lam; 10. Water and sanitation Frank Rijsberman and Alix Peterson Zwane; 10.1 Alternative perspective W. Michael Hanemann; 10.2 Alternative perspective Guy Hutton; 11. Corruption and policy reform Susan Rose-Ackerman and Rory Truex; 12. Trade barriers and subsidies: multilateral and regional reform opportunities Kym Anderson; Part II. Ranking the Opportunities: Expert Panel Ranking Finn E. Kydland, Robert Mundell, Thomas Schelling, Vernon Smith and Nancy Stokey; Conclusion: making your own prioritisation Bjorn Lomborg; Index.