Following a review of treatments for benign prostatic hyperplasia (BPH) by the Medical Advisory Secretariat (MAS) of the Ontario Ministry of Health and Long-Term Care (MOHLTC), the Ontario Health Technology Advisory Committee (OHTAC) recommended that "a registry study be conducted to establish longer term effectiveness and complication rates for PVP given the likelihood of increasing diffusion of this technology". Since then, the Medical Devices Bureau of the Therapeutic Products Directorate, Health Canada, has licensed in April 30, 2007, a 120W-KTP laser system (Greenlight HPS (TM)) for sale in Canada. As several new 120W systems will be operating in Ontario in the coming months, there is an urgent need to evaluate the effectiveness, cost-effectiveness and durability of 120W PVP compared to conventional TURP in the treatment of patients with BPH.