The photodissociation dynamics of the NaI(H2O) dimer is studied theoretically. The dynamics are simulated via the "molecular dynamics with quantum transitions" trajectory method of Tully and co-workers in order to describe nonadiabatic transitions between the excited and ground electronic states. In the calculations, the electronic structure of NaI is determined at every point along trajectories by semiempirical valence-bond theory, while the water is described by classical potentials. It is found that the clustered water enhances the probability of an excited-to-ground-state nonadiabatic transition compared to the isolated NaI case. In addition, the clear oscillatory dynamics for the bound excited state motion for isolated NaI is considerably muted by the presence of the water. Other characteristic features of the process include a considerable transfer of rotational kinetic energy to the water molecule and a rapid "evaporation" of that molecule. These latter characteristic features are shown to arise from a reversed polarity of the Franck-Condon excited state NaI compared with the ground state polarity Na+deltaI-delta.