Binding or dissociation energies of the ground state, S-0, the first electronic excited state, S-1, and the ion ground state, I-0, of the p-methoxyphenetylamine(H2O)(1-4) complexes, referred to henceforth as either MPEA(H2O)(1-4) or by their stoichiometric ratios 1:1-4, have been analyzed by threshold ion fragmentation. MPEA(H2O)(1-4) complexes were prepared by the supersonic expansion of premixed samples containing appropriate amounts of MPEA and water molecules into carrier gas He. A number of isomers, with characteristic 0(0)(0) transition energies, have been identified: two for MPEA(H2O)(2) at 35 676 and 35 689 cm(-1), one for MPEA(H2O)(2) at 35 687, one for MPEA(H2O)(3) at 35 571 and two for MPEA(H2O)(4) at 35 419 and 35 422 cm(-1) respectively. The ionization energy and fragmentation thresholds, the latter defined as the onset energy of the process MPEA(H2O)(n)* + hv--> MPEA(H2O)(n-1)(+) + H2O, have been determined, and from them the dissociation energies for the set of MPEA(H2O)(1-4) isomers in their ground state, first electronic excited states, and ion ground states were readily obtained. The set of values are compared with those computed for the water association complexes.