At a time of global climate crisis, this crucial book examines the prospects for implementing low-carbon policies in the two global superpowers of China and Russia, focusing on the role of informal institutions in achieving reductions in greenhouse gas emissions. Chapters shed light on how informal institutions function and work in practice, how and why they take shape and how they influence formal low-carbon policies. Forensically examining five critical cases relating to Chinese and Russian institutions, this book demonstrates how informal institutions can both support and obstruct the achievement of formal policy goals. Through comparisons within and between each country, it shows how these dynamics differ and offers key hypotheses on the role of these institutions in policy implementation. Comprehensive and incisive, this book will be important reading for scholars researching public policy in China and Russia, particularly those specialising in environmental science and politics. The practical insights derived from new case studies will also be useful for policymakers working on climate mitigation policy.