These proceedings comprise cutting-edge contributions by researchers at the frontiers of beam physics, free-electron-based light sources, and advanced accelerators. It represents a snap-shot of activity in these fields at a critical historical juncture, where rapid experimental progress is being reported, and new facilities such as X-ray free-electron lasers are under construction. The volume features invited contributions from leading researchers from the international beam physics community that summarize the state-of-the-art research in individual topics, as well as timely contributions from participants that arose during the workshop itself.