In 2015, Milan will host the Universal Exposition, Expo 2015, titled “Feeding the planet, energy for life”. As the 19th Metropolis conference takes place one year ahead, it is to introduce Expo 2015 and to emphasize the significance of movements of people in the early years of this new millennium. That is, movement of persons is a fact, a distinctive element of a henceforth international society. Despite the challenges posed by the management of such movements in terms of flows, integration or else social cohesion, the Metropolis project recognizes the opportunities diversity represents. Acknowledging the centrality and plurality of cultures, the conference wants to highlight the contribution in terms of energy and wealth that migrations bring about.