Preparing metropolitan cities like Paris for the heating up of the globe due to climate change is a huge task. As early as 2020 Paris started an ambitious greening program. 170.000 new trees by 2026 in a densely populated city is a steep challenge. With 114.000 trees planted by 2024 as the Olympic athletes and spectators gathered in Paris the city is right on track. The 2 parks “bois de Boulogne et bois de Vincennes” have jointly 25.000 new or renewed trees. The cemeteries, for example “Père Lachaise” has received new cooling trees as well. Most trees, however, were planted along the notoriously hot and overcrowded “périphérique” with 50.000. Only with the use of a Colbert-like planning exercise and rigorous implementation against even some initial resistance, it is possible to achieve this result and the ultimate objective. Visitors of the Olympic Games already experienced the differences during the summer of 2024. Detailed planning by means of a “Bilan par arrondissement” facilitates monitoring of progress. Publishing the information is part of the communication strategy to keep citizens informed and engaged in this silent transformation for the benefit of inhabitants and visitors. (Image City of Paris webpage 2024)