Percutaneous approaches to lumbar discectomy were somewhat controversial, because of their limited indications. They have not proven to be as effective as standard open lumbar disc surgery, because of longer operating times and some technical problems in addressing all the different aspects of lumbar disc herniations. New percutaneous posterior procedures for lumbar disc disease have been described in the last few years, but the MicroEndoscopic Discectomy (MED) introduced by Foley and Smith in 1997 seems to be the most promising one. MED, and METR’x which evolved from it, . allow the surgeon to address not only contained lumbar disc herniations, but also free-fragment disc pathology and symptomatic lateral recess stenosis secondary to bony hypertrophy. The surgical technique is summarized and some preliminary clinical results of a prospective multicenter study with 13 months’ mean follow-up are presented.