  We explore the possibility that a CP violating phase of the neutrino mass
matrix is promoted to a pseudo-Goldstone-boson field and is identified as the
quintessence field for Dark Energy. By requiring that the quintessence
potential be calculable from a Lagrangian, and that the extreme flatness of the
potential be stable under radiative corrections, we are led to an essentially
unique model. Lepton number is violated only by Majorana masses of light,
right-handed neutrinos, comparable to the Dirac masses that mix right- with
left-handed neutrinos. We outline the rich and constrained neutrino
phenomenology that results from this proposal.
