Neutrino mixing and CP-violation

The prospects of measuring the leptonic angles and CP-odd phases at a neutr ino factory are discussed in two scenarios: (1) three active neutrinos as i ndicated by the present ensemble of atmospheric plus solar data: (2) three active plus one sterile neutrino when the LSND signal is also taken into ac count. For the latter we develop one and two mass dominance approximations. The appearance of wrong sign muons in long baseline experiments and tau le ptons in short baseline ones provides the best tests of CP-violation in sce narios (1) and (2), respectively. (C) 2000 Elsevier Science B.V. All rights reserved.