Techniques for selecting electrode combinations for stimulation therapy include delivering stimulation via each of at least five combination groups. A first group of electrode combinations is characterized by the presence of a caudal anode. A second group of electrode combinations is characterized by the presence of a rostral anode. A third group of electrode combinations is characterized by the presence of a single anode above and a single anode below the cathode(s) of the combination. A fourth group of electrode combinations is characterized by the presence of multiple anodes above and below the cathode(s) of the combination. A fifth group of electrode combinations is characterized by the presence of transverse anodes. A sixth group of electrode combination is characterized by at least one off-center cathode. One or more preferred electrode combinations groups, and/or a number of leads to implant within the patient, may by selected based on patient feedback.