Political will has been critical for protecting forests in the Brazilian Amazon and Indonesia

Deforestation remains a prominent contributor to climate change and biodiversity loss. Yet while 76 million hectares of primary tropical forest have been lost since 2000, two thirds of tropical forests remain. What factors have been most important for protecting these forests? Unlike policies, which often have clearly defined spatial and temporal boundaries, the roles played by dynamic underlying political and economic structures, and their interactions with policies and emergent factors, can be challenging to identify. Expert knowledge can bridge this gap by revealing the full range of factors needed to achieve forest protection. Here, we conducted a Delphi study with 36 experts, focusing on the Brazilian Amazon and Indonesia. Our results highlight the importance of political will, civil society advocacy, and intergovernmental diplomacy, and shifts in the importance of different factors over time. These findings illuminate the interactions between international and national structures and policies in generating the conditions for forest protection.