The three-potential surface problem of electron transfer in solution is analyzed using Zusman-type kinetic equations. The model describes ultrafast formation and recombination of radical–ion pairs limited by solvent dielectric relaxation. The problem begins with a donor on an electronic excited state surface. The system evolves with crossing to the radical–ion pair surface (with the possibility of recrossing to the excited donor surface included). Solvent relaxation moves the system to lower energy on the radical–ion pair surface where crossing to the ground state neutral surface occurs (with the possibility of recrossing to the radical–ion surface included). Model calculations of the transient radical–ion pair populations are presented. The time dependent results that are presented show a dramatic dependence on the relative free energy differences (ΔG’s) among the three potential surfaces. Comparisons to other formalisms and to less detailed approximations are made. The mean populations of the transient species for a system of a donor and many acceptors in the absence of spatial diffusion are also derived.