This study examined efficacy and safety of the 980 nm side-firing diode laser operating at a power of 100 W in patients with lower urinary tract symptoms associated with benign prostatic hyperplasia (BPH). Patients were selected for surgery on the basis of maximum urinary flow rate (Qmax) p15 ml/s or transvesically measured post-voiding residual volume (PVR) 4100 ml in conjunction with an International Prostate Symptom Score (IPSS) 47. Laser therapy was conducted under spinal anaesthesia. Qmax, IPSS, prostate volume, PVR, IPSS-Quality of Life (QoL) questionnaire and ejaculatory function were measured at baseline and at 1, 3, 6 and 12 months post-laser therapy. A total of 52 consecutive patients aged 52-65 years with mean (s.d.) prostate volume of 45.14 (9.15) g were treated. All patients were able to leave the hospital at a mean (s.d.) of 5 (2) h after the procedure. Mean (s.d.) follow-up was 100 (75.49) days. A significant reduction in IPPS was reported at 1 month (Po0.0001) and this was maintained through to 6 months. Significant durable improvements in Qmax, PVR and IPSS-QoL score were also reported for all patients (Po0.0001). No severe complications were reported, including any cases of urinary incontinence or significant irritative symptoms. None of the patients complained of a worsening of erectile function. This early experience in a pilot study with the 980 nm diode laser seems promising in the short-term and long-term outcome is being monitored.