A cometary nucleus spin state may be primordial or significantly modified by torques produced by selective directed outgassing. Since direct spacecraft observations are rather sparse, groundbased observations are important in indirectly determining or constraining possible nucleus spin states. We review groundbased methods for estimating nucleus spin states and discuss their inherent uncertainties. These methods include photometry of the inactive nucleus, photometry of coma brightness variations, changes in coma morphology and interpreting non-gravitational perturbations on the orbit. We will review examples of these methods as applied to specific comets and problems relating to designing experiments. For example, photometry of periodic activity in the coma is sensitive to spatial(the effective aperture size) and temporal sampling. Photometry of inactive nuclei require large telescopes capable of accurate photometry and appropriate temporal sampling when the comet is at large heliocentric distances. Interpreting changing coma morphology requires knowledge or assumptions of several independent variables such as particle size distribution and diurnal production variations of active areas. In the future, new large aperture telescopes may offer expanded opportunities in this field.