Tree growing has become one of the most widely promoted responses to climate change and ecosystem degradation, with governments, companies and nonprofits pledging to restore hundreds of millions of hectares of forests worldwide. But restoring ecosystems is far more complex than putting seedlings in the ground. This Special examines what it takes to rebuild forest ecosystems in ways that benefit climate, wildlife and people. Join Mongabay journalists as they dig into the science, practices, policies and institutions shaping global restoration efforts to unearth how tree-planting pledges are measured, how restoration projects affect biodiversity and livelihoods, and why some initiatives succeed while others fall short.This article was originally published on Mongabay