The reunification of 10 faculty libraries inside the new Rolex Learning Center at EPFL (Lausanne, Switzerland) was a perfect opportunity to rethink which collections should be put forward in an environment that is organized primarily around the working and living space of users. Meanwhile, "Collection development" has shifted from a simple selection and subsequent acquisition of content to a selection of the best way to offer access to relevant content. Electronic books allow on-demand access in an even more cost and resource-efficient way. We will discuss how the EPFL Library is implementing its e-books collection to allow for on-demand access and how to provide total transparency for the users.