The purpose of these Lecture series in Public Policy is to give students opportunities to interact with high public policy experts in areas related to the use of data. These meetings will allow both a return on past experiences but also a direct transfer of knowledge on projects that are still in progress. Through these testimonies, we will be focused not only on technical but also concrete and human aspects of data management in public policies. To make the most of these Lecture series, students will be central actors: they will have to draw up a portrait of the guest, introduce his or her subject during a short joust, contribute to animate the debate and make a reflexive report of it.