An external control device for use with a neurostimulation system having a plurality of electrodes capable of conveying an electrical stimulation field into tissue in which the electrodes are implanted is provided. The external control device comprises a user interface having one or more control elements, a processor configured for generating stimulation parameters designed to modify the electrical stimulation field relative to one or more neurostimulation leads carrying the electrodes. The external control device further comprises output circuitry configured for transmitting the stimulation parameters to the neurostimulation system.