1. An external system for treating a patient suffering from tremor, the system comprising: a pulse generator; and a circumferential band adapted to be secured to the patient's arm or wrist, the band supporting a first and a second electrode in electrical communication with the pulse generator, the first and second electrodes being spaced on the band and configured to deliver electrical stimuli from the pulse generator to the patient to preferentially excite a first nerve selected from the patient's median, radial or ulnar nerve, the first and second electrodes being arranged and configured such that in a transverse cross-sectional plane of the arm or wrist there is a 90 degree to 180 degree angle between a line connecting the first nerve and the first electrode and a line connecting the first nerve and the second electrode.