The articles contained in this volume represent the work performed in the years 2000-2003 on the ECFA sponsored study of a 'European Neutrino Factory Complex'. Future neutrino facilities for Europe invariably encompass a high-intensity proton driver. They can develop progressively, starting from a low-energy neutrino superbeam, via beta beams, to a neutrino factory and muon colliders based on muon storage rings. The ambitious and broad physics programme ranges from cutting-edge nuclear physics and muon physics to leptonic CP violation. The accelerator complex, neutrino oscillation experiments, precision study of neutrino interactions, low-energy muon experiments, kaon physics and muon collider physics are described in tum.