Last week's Rio+20 sustainable development conference in Brazil pledged to protect the world's forests by promoting secure land tenure. Many conservationists were disappointed that the nonbinding declaration left an opening for conversion of natural forests to industrial use and building infrastructure. But China has already implemented substantial tenure reforms, aiming to revitalize China's rural economy while throwing a lifeline to tattered forest ecosystems, and no other country's efforts may prove more critical. The reforms allow villages to determine tenure rights in the roughly 60% of China's forestland that has been collectively owned for decades, affecting about 100 million hectares and some 400 million people. Early signs suggest that the reforms are boosting land productivity and forest cover. But some experts caution that the reforms create the potential for forest fragmentation and complicate the task of sustainable management.