  We derive the lepton number violating dimension-five and dimension-seven
operators, relevant for neutrino mass generation, in the Minimal Supersymmetry
Standard Model without R-parity (the $/R$MSSM) by using the effective
Lagrangian method. We keep all the possible CP violating phases, and we
establish the general relationship between the high-scale parameters and the
low-energy observals associated with the Standard Model particles. We study in
a specific model the dependence of neutrino masses on the CP phases.
