  Models of spontaneous CP violation can solve the Strong CP problem without
the need of an anomalous Peccei-Quinn symmetry. In this work we review the
Nelson-Barr approach, quantifying a peculiar coincidence between unrelated mass
scales that these models must satisfy in order to correctly reproduce the
Standard Model quark masses and CP violation. We investigate the compatibility
between this requirement and the induced radiative corrections to the neutron
electric dipole moment, and with bounds coming from collider, electroweak and
flavor observables.
