With energy powering the most attractive aspects of urban environments in modern society, from health, transportation, and comfort to information, business, and leisure, energy cities are perfectly positioned to design the smart city of the future by leveraging the energy foundations of the city. This chapter focuses on the emerging concept of energy cities through the lens of sustainable behaviors and their role in alleviating climate change. We use the results of a randomized control trial experiment implemented in Monaco to illustrate our arguments on the role of behavioral intervention in empowering citizens on the importance of saving energy. The results will offer a vision of what steps cities are taking to increase environmental awareness and the role of individual behaviors in tackling climate change.