We have applied high-level coupled cluster methods, in conjunction with a variety of reference molecular orbitals and basis sets, to consider the possibility that the equilibrium geometry of the ground state Of ScO2 breaks C-2v symmetry. The force constants for the antisymmetric stretching vibration (b(2) symmetry) have been computed across a domain of Sc-O bond distances and O-Sc-O bond angles at the spin-restricted open-shell Hartree-Fock (ROHF) and spin-unrestricted Hartree-Fock (UHF) levels of theory in order to investigate the importance of artifactual orbital instability envelopes on the properties computed with correlated wave functions. In most cases, Hartree-Fock instability regions are located far from the pertinent optimized geometries, suggesting that the corresponding harmonic vibrational frequencies; should be free from artifactual orbital effects. Nevertheless, ROHF- and UHF-based coupled cluster models disagree qualitatively on the symmetry Of ScO2, and Brueckner orbital based methods give variable results with respect to basis set and level of electron correlation. Although full coupled cluster single-, double-, and triple-excitation results indicate symmetry breaking with smaller basis sets, extrapolation of the results to larger basis sets is inconclusive. The current results indicate with certainty only a flat symmetry-breaking potential. Furthermore, although all methods considered here predict that C-s optimized structures lie lower in energy than their C-2v counterparts, the highest levels of theory predict very low effective barriers to interconversion of equivalent C-s minima-low enough that the zero-point vibrational energy (even when computed with anharmonicity corrections) lies above the barrier leading to an overall dynamical C(2)v symmetry.