The structures of water clusters varying in size from n = 2 to n = 6 (cyclic, prism, and cage isomers) have been redetermined on a counterpoise-corrected potential energy surface and result in oxygen-oxygen distances that are some 0.1 Angstrom longer than would otherwise be found. NMR shielding calculations have also been carried out on the reoptimized structures and show that the shieldings of the hydrogen bonded protons tend to reproduce the gas-to-liquid shielding change observed for water, whereas those for oxygen do not. Use of the COSMO self-consistent reaction field to determine additional shielding changes does not significantly improve the situation.