  We show that in Sr2RuO4 the Fermi surface geometry as inferred from angle
resolved photoemission experiments has important implications for a pairing
interaction dominated by incommensurate, strongly anisotropic, spin
fluctuations. For a spin fluctuation spectrum consistent with inelastic neutron
scattering experiments the system is close to an accidental degeneracy between
even parity spin singlet and odd parity spin triplet channels. This opens the
possibility of a mixed parity order parameter state in Sr2RuO4. We determine
the stable and metastable order parameter phases at low temperatures and
discuss especially phases with order parameter nodes.
