The singles and doubles coupled-cluster method that includes a perturbational correction for connected triple excitations, denoted CCSD(T), is used in conjunction with several one-particle basis sets to determine quartic force fields for OH-. Basis set convergence properties of the various rovibrational spectroscopic constants is studied. To assure numerical stability of the quartic force fields and to investigate variational calculations of vibrational energy levels, sextic force fields have also been evaluated. The largest one-particle basis set employed contains up through h functions on oxygen and g functions on hydrogen. Agreement between experiment and theory is excellent and it is shown that the CCSD(T)/spdfg approach performs as well for OH- as it previously did for H2O. Due to the inherent difficulty in high resolution studies on molecular anions, it is concluded that currently the CCSD(T)/spdfg approach may be the most reliable technique for the determination of accurate rovibrational spectroscopic properties of small-to medium-sized anions. (C) 1997 American Institute of Physics.