The present invention relates generally to a therapeutic pulse generator system used to provide energy efficient stimulation/pacing by causing controlled cellular depolarization based on pre-measured charge transfer. This is accomplished by periodic electrical characterization of the electrode-tissue interface. Each channel of stimulation is programmed individually enabling the clinician to customize the therapeutic protocol. Energy efficiency may also be further improved through the use of a multi-channel lead in which the amount of energy required for each subsequent channel may be set to be less than the previous channel. The total energy required for multi-channel stimulation/pacing has also been shown to be less than that required by a single channel for the same therapeutic benefit.