The theor. foundations and the implementation of a computer program for generalized-self-consistent-reaction-field (GSCRF) calcns. are described. The GSCRF model takes the microscopic structure of the environment of a solute explicitly into account; it models electrostatic interaction between the ab-initio described solute and the classical solvent by distributed multipole moments, and represents induction effects by elec. polarizabilities of individual solvent mols. High-precision solute wave functions can be calcd. at arbitrary level of theory in realistic solvent models. As examples, the proton transfer of NH3...HCl in argon matrix and the electrostatic properties (dipole moment, quadrupole moment) of a water mol. in liq. water are discussed.