Hydration of the atomic oxygen radical anion is studied with computational electronic structure methods, considering (O-)(H2O)(n) clusters and related proton-transferred (OH-)(OH)(H2O)(n-1) clusters having n = 1-5. A total of 67 distinct local-minimum structures having various interesting hydrogen bonding motifs are obtained and analyzed. On the basis of the most stable form of each type, (O-)(H2O)(n) clusters are energetically favored, although for n >= 3, there is considerable overlap in energy between other members of the (O-)(H2O)(n) family and various members of the (OH-)(OH)(H2O)(n-1) family. In the lower-energy (O-)(H2O)(n) clusters, the hydrogen bonding arrangement about the oxygen anion center tends to be planar, leaving the oxygen anion p-like orbital containing the unpaired electron uninvolved in hydrogen bonding with any water molecule. In (OH-)(OH)(H2O)(n-1) clusters, on the other hand, nonplanar arrangements are the rule about the anionic oxygen center that accepts hydrogen bonds. No instances are found of OH- acting as a hydrogen bond donor. Those OH bonds that form hydrogen bonds to an anionic O- or OH- center are significantly stretched from their equilibrium value in isolated water or hydroxyl. A quantitative inverse correlation is established for all hydrogen bonds between the amount of the OH bond stretch and the distance to the other oxygen involved in the hydrogen bond.