There has been an emergence of smart cities as a particular kind of city in response to the complex development needs of today’s dynamic multifunctional communities. The 2030 Agenda for Sustainable Development sets out under its 11th goal—Building Sustainable Cities and Communities—the worldwide relevant target reference used to understand better the needs of a smart city. The definition of the stakeholder community’s vision about the future shape of the city and the systems making it a smart city is one of the key stages in smart city development. City foresight is viewed as the science of thinking about the future of cities. Many urban communities’ resort to foresight exercises as they help highlight and aggregate the needs of multiple stakeholders, suggest innovative solutions, and define a time horizon needed for developing realistic initiatives for city transformation. City foresight enables the exploration of alternative development paths, and therefore provides practical tools for policy-makers to enhance their decision-making capabilities by using different scenario design exercises and exploratory hypotheses. The objective of this chapter is to shed light on the salience of foresight exercises in the transformation of cities into smart cities. For this purpose, we have systematized the foresight exercises and have made theoretical clarifications and classifications of forecast data, activities, and techniques used in city foresight, underlining the importance of foresight exercises for smart cities and their benefits. This systematization is useful for understanding the multiple alternatives, from which one can choose in order to define a foresight exercise, prior to putting forward practical initiatives transforming the city systems and public governance policies for a smart city.