Sustainability starts in the municipalities, as they form the basis for the implementation of the 17 SDGs and their 169 sub objectives. In the municipalities—where people live, work, spend their leisure time, and where they have their friends and families—the concern for sustainability is greatest. Ultimately, it is the cities, counties, and municipalities which will decide whether sustainable development will be a success. That is why the manner in which communities address sustainability and the implementation of the SDGs is of central importance. Consequently, the High Level Political Forum on Sustainable Development (HLPF) of the United Nations states: “It is in the cities where the struggle for sustainable development will be won or lost.” Or to put it another way: It is in the cities where undesirable outcomes and problems, but also successes, become visible—as if seen through a magnifying glass.