Cities provide plentiful economic and social opportunities, but they also have large environmental footprints. A central question for the success of the 2030 Agenda is hence how we can create more sustainable cities. People are the key to this process. Only if residents in cities can be supported to change their behaviour can sustainability goals be achieved. In this seminar, we will discuss how to design built environments that successfully encourage people to change habits and behave in a more sustainable way. This includes initiatives to minimize car use, to consume less energy and water, and to reduce waste. On 10 February 2021, during the fifth in a series of Agenda 2030 dedicated webinars, together with a series of experts and speakers, trends and challenges in planning for green cities with the Norwegian Association of Local and Regional Authorities.