Abstract: A power supply for a high intensity discharge lamp is provided wherein the secondary windings of a pair of lamp strike pulse transformers are connected in series with the HID lamp directly across the AC supply, the impedance of these secondary windings acting as the only ballast elements of the power supply. The HID lamp is chosen to have relatively high operating and maximum starting currents so that warm-up time of the lamp is dramatically reduced while employing the lamp strike pulse transformers to perform the dual function of starting the lamp when either hot or cold and acting as the current limiting ballast for the lamp both during warm-up and under normal operating conditions.