New electronic states of H2O and D20 have been identified in the energy range from 84,000 to 88,000 per cm as three-photon resonances by four-photon ionization spectroscopy. The rotational energy distributions of the states Bi and A2 are simulated using asymmetric top three-photon line strength theory and rotational analyses. Rydberg states are assigned to the excitations 4sa(1) - 1b(D prime 1B1-X1A1) and 3db2 1b1(D-double-prime 1A2-X1A1), based on equilibrium geometries, quantum defects, and the polarization dependence of the transition probabilities. The identification of a one-photon 1A2-1A1 transition, permits the assignment of all five members of the 3d - 1b1 complex. The heterogeneous and homogeneous predissociation behavior of the D-prime and D-double-prime states is also considered.