The development of industrial excimer-and CO2 TEA pulse lasers with average optical powers in the kilowatt range, requires pulsing circuits delivering average power levels of tens of kilowatt. Excitation pulses with voltage rise times in the order of 100 ns and peak voltages of more than 40 kV are required for efficient operation of the laser. To meet these requirements, primary switching must be carried out at tens of kA, at voltage levels in excess of 40 kV, and at repetition rates of several kHz. These requirements place extreme demands on the active switching elements employed in the pulser for primary pulse conversion. Traditionally, thyratrons have been used as switching elements. However, under these operating conditions, their lifetimes are drastically limited, making them not a commercially viable choice. Endeavours to overcome these limitations have led to the development of an all solid-state driven pulser. This pulser makes use of a modular, thyristor switched, pulse power supply unit for primary pulse conversion. Pulses of 40 μs duration are supplied to a four-stage series magnetic pulse compressor to transform the pulses down to 150 ns for efficient laser excitation.