 It's a wicked problem. Tropical countries need to reduce deforestation while meeting development goals and reducing poverty. Everyone needs to work together, governments and the private sector, with the support of civil society. The drivers of deforestation vary, from palm oil in Indonesia to beef and soy in Brazil, but there's a lot tropical countries can learn from each other. Brazil reduced annual deforestation in the Amazon by 77% in seven years, and since 2011, it's stabilized at 5,000 square kilometres per year. How did they do it? Better satellite monitoring of illegal logging, strict enforcement of the laws, a moratorium on soy expansion into forest lands, and public-private collaboration to promote sustainable beef production. About 60% of deforested land in the Brazilian Amazon is now pasture. 20% of the cattle herds on that land belong to small holders. According to law, producers are meant to set aside some of their land as forest. That wasn't always happening until the private sector stepped up. In 2009, supermarkets began to suspend contracts with suppliers linked to Amazon deforestation. Parts of the beef industry pressured landholders to comply with environmental laws by only buying certified legal beef. So large numbers of landholders signed voluntary commitments to protect or restore their forest in alignment with the new forest code. The fact is that these sectors are very concentrated, so a small number of large-scale companies that make the commitment to moving that direction helps a lot. These public-private interactions are one of the key to understand the success in the Brazilian case. The challenge for Brazil now is to produce more, better quality beef on less land without increasing reliance on chemical fertilizers and herbicides. That is possible with the right incentives, but they need to target rural farmers, not just big companies. Reducing deforestation in primary forests, improving livelihoods for small holders and expanding supply to meet a growing demand. Each of these challenges affects the others. Wicked problems need complex solutions, solutions that will only be found if governments, private sector and civil society work together to meet these interconnected challenges.