The International Design Study for a Neutrino Factory (IDS-NF) has been an international multi-disciplinary effort that has been considering the best possible design for a Neutrino Factory, a neutrino beam facility from the decay of muons for the study of neutrino oscillations, with the ultimate goal of discovering CP violation in the neutrino sector. In this talk, I will summarise the evolution of the Neutrino Factory concept derived from the 10 GeV muon beam IDS-NF, which provides the best possible sensitivity for the discovery of CP violation in the neutrino sector, towards a realistic staging scenario, which would include as a first stage the nuSTORM (Neutrinos from STORed Muons) facility and would evolve towards a 5 GeV muon facility (NuMAX) that has the potential to discover CP violation in the neutrino sector. The physics reach of each of the facilities will be discussed.