The present paper aims to do a parallel between the city of New York and Sao Paulo, which are cities that, in a comparative model, have many differences when it comes to the application of the concepts of smart cities and the objectives of the 2030 Agenda. Speaking in the smart city refers to the idea of safety, modern means of transport with reduction or neutralization in the emission of greenhouse gases, greater locomotive technology, economy, social cohesion, use of renewable energy methods, and greater contact of human beings with nature, as exposed in the IESE Cities in Motion Index 2020. The article will present the notion of a Smart City and will assess whether the cities of New York and Sao Paulo fulfill the requirements to fit into the notion of smart cities. In the end, the text will demonstrate the importance of behavioral regulation, with an emphasis on nudges, for the implementation of smart cities.