An electrosurgical system comprises an electrosurgical probe and an electrosurgical power supply for ablation and resection of soft tissue in the presence of electrically conductive fluids, such as isotonic saline. In one embodiment, the probe includes a shaft having an electrode array with a plurality of electrically isolated electrode terminals and a return electrode spaced proximally from the electrode array. The power supply includes a plurality of current limiting elements for limiting current based on impedance between the electrode terminals and the return electrode. By applying high frequency voltage to the electrode array, target tissue may be cut or ablated while heat dissipation through low impedance paths, such as saline, is minimized. The power supply has an operating frequency less than 400 kHz, usually about 100 kHz, for limiting current penetration into the tissue.