We have made a Nd:YAG laser which operates in a cw mode, a pulsed mode, and a mixture of the two. This has been achieved by mixing the dc and the pulsed pumping currents. A thyristor-switched pulse power supply and a cw power supply are isolated from each other with high-current diodes. The output performance of the three modes has been compared by varying the reflectivities of the output mirrors. Two kinds of lamp, a specially designed flashlamp and an arclamp, were used in optimizing the output power. A peak power as high as 3.6 kW has been obtained in the mixed-mode operation with a Kr flashlamp at 2-atm pressure.