We would like to extend our great appreciation to the external experts participating in the Policy Delphi: Eva Heiskanen, Heta Heiskanen, Sarah Olson, Antti Kinnunen, Meri Löyttyniemi, Mats Björsell, Søren Løkke, Jessika Richter, Magnus Bengtsson, Juudit Ottelin, Frode Longva, Robert Höglund, Marit Widman, Johan Stensson, Mònica Guillen-Royo, Jamil Khan, Katarina Eckerberg and Maria Sandow. Thanks a lot to Emil Dæhlin for his input on Norwegian statistics and to Megan Eardley and Lakin Anderson for editing and to Ida-Lina Strang for layout. Last but certainly not least, many thanks to the secretariat as well as the members of the Nordic Working Group for Environment and Economy (NME) and the Nordic Working Group for Climate and Air (NKL) under the Nordic Council of Ministers for fruitful discussions. Your comments and constructive critique helped us along the way. All remaining errors are solely our own. Eskil Engström and Markus Larsson are the main authors of this report and contributed equally. Other co-authors have contributed with written texts, comments and edits.