The process of setting up a digital preservation repository in compliancy with the OAIS model is not only a technical challenge: libraries also need to develop and maintain appropriate skills and organization. Digital activities, including digital preservation, are nowadays moving into the mainstream activity of the Library and are integrated in its workflows. The Bibliothèque nationale de France (BnF) has been working on the definition of digital preservation activities since 2003. This paper aims at presenting the organizational and human resources challenges that have been faced by the library in this context, and those that are still awaiting us. The library has been facing these challenges through a variety of actions at different levels : organizational changes, training sessions, dedicated working group and task forces, analysis of skills and processes, etc. The results of these actions provide insights on how a national library is going digital, and what is needed to further accomplish this essential change.