A historical review of both laboratory and clinical wear performance of orthopaedic bearing materials and surfaces is presented. Over time, laboratory wear tests have been developed and used more frequently to support the introduction of new material couples. Historically, these methods have been unreliable, and, despite recent improvements, predicting clinical wear performance is still a challenging task. Orthopaedic wear is a highly multi-factorial process-successful simulation depends on the identification, modeling, and control of many critical factors. Clinical results themselves an highly variable, complicating efforts to establish clinical validation criteria for test methods. It is recommended that improvements be made in identifying the appropriate clinical targets for laboratory tests, and that increased effort be directed toward the optimization and standardization of wear test methods.