How can cities leverage their data to address pressing local problems? This was the question that representatives of several European cities, among them Vienna, Dublin, Prato and Lyon, tried to answer at a workshop in Florence on 25-26 January 2018. Matteo Satta from Issy-les-Moulineaux was also at the event. From running state-of-the-art data portal to participation in countless national and EU projects, the French city has a long-standing experience with data driven innovation. The workshop was therefore a perfect opportunity to share all the knowledge accumulated over the years with the audience of like-minded innovation enthusiasts. The latter were particularly impressed by the PoliVisu Issy pilot, which focuses on data mash-ups, analysis and traffic prediction, seeing in it great potential to improve travel experience for commuters during the ongoing construction of Grand Paris Express. The details of all three PoliVisu pilots (the other two being Ghent and Pilsen) will soon be available online. In the meantime, read our vision to see how your city can benefit from the project!