Passive B1+ shimming was performed using custom dielectric pads to improve image uniformity for clinical knee imaging at 7T. Image non-uniformity is problematic for diagnosing knee pathologies, and post-processing solutions are limited at 7T due to the lack of a uniform body transmit coil. A range of pads made from high permittivity perovskite materials were fabricated and tested on 6 subjects. An optimal configuration was determined, comprising the pad dimensions and composition, commensurate with producing optimal image uniformity while fitting all subjects scanned. Dielectric pads represent an easy-to-use solution for improving clinical image uniformity at 7T.