Treatment apparatus and methods for delivering energy at multiple selectable tissue depths as selected by a clinician. The treatment apparatus includes at least two electrodes that are electrically isolated from each other, which permits each electrode to be independently energized for selecting different treatment depths. The electrodes may be concurrently energized with high frequency energy of the same polarity in a monopolar mode to deliver energy at a relatively deep depth into a patients tissue, or with high frequency energy of a different polarity in a bipolar mode to provide a shallower penetration depth. Alternatively, the depth of energy delivery may be modified by energizing less than all of the electrodes. The electrodes may be energized with high frequency energy of different phase relationships to deliver energy concurrently in both monopolar and bipolar modes with the phase difference determining a depth of energy delivery.
