The idea to produce a joint edited volume arose in early 2018. In June 2018, we could already discuss first draft chapters at a two-day workshop, which was kindly hosted by Harro van Asselt and Cleo Verkuijl at the Oxford branch of the Stockholm Environment Institute. The process of writing this book over the following year has been a stimulating, fruitful, and intense academic journey and conversation, which has cut across and bridged different scholarly fields such as international relations, environmental politics, law, geography, and environmental sciences. We presented our revised book chapters in a panel organized at the annual meeting of International Studies Association (ISA) in Toronto in March 2019 and want to express our gratitude to our discussant Matt Hoffmann from the University of Toronto. He provided extremely useful and excellent feedback that helped us to enhance the contributions to this book during the final steps before the submission of our manuscript.