Abstract: Devices, systems, and techniques are disclosed for planning, updating, and delivering electric field therapy. In one example, a system comprises processing circuitry configured to receive a request to deliver alternating electric field (AEF) therapy and determine therapy parameter values that define the AEF therapy, wherein the AEF therapy comprises delivery of a first electric field and a second electric field. The processing circuitry may also be configured to control an implantable medical device to deliver the first electric field from a first electrode combination of implanted electrodes and control the implantable medical device to deliver, alternating with the first electric field, the second electric field from a second electrode combination of implanted electrodes different than the first electrode combination.