The disclosure pertains to an intravascular catheter for nerve modulation, comprising an elongate member having a proximal end and a distal end, a balloon having a lumen and a balloon wall, the balloon wall comprising RF permeable sections and non-electrically conductive sections, an electrode disposed within the balloon and extending distally to the furthest distal RF permeable section. The RF permeable sections may comprise a plurality of RF permeable windows, each window having a greater circumferential dimension than an axial dimension. The intravascular system is suited for modulation of renal nerves.