Abstract: A dimming system, which provides a time-varying current from a power source between the electrodes of a gas discharge lamp, simultaneously provides high-frequency, low-level current between the electrodes to sustain an electric discharge in the lamp when the time varying current alone is insufficient. The system provides reduced starting stress in the lamp and, therefore, longer lamp life by delaying the formation of an arc discharge, during start-up, until the electrodes have been heated. The system can be used with standard magnetic ballasts to provide full-range dimming of gas discharge lamps from 3 to 100 percent light output with minimal striations, lamp drop out, and flicker.