Interstitial laser-induced coagulation (ILC) is a new, minimally invasive, procedure for the treatment of benign prostatic hyperplasia (BPH). It is based on the placement of special light guides in the prostatic tissue, either transurethrally or perineally. The radiation source is a Nd-YAG laser, which is active for 3 or 5 min per fiber placement, respectively, with the power reduced stepwise. The coagulation necroses caused shrink during follow-up, leading to a decrease in the obstruction. In 239 patients treated in this way the mean I-PSS-Score fell from 25.4 to 8.1 points and the quality of life index from 4.1 to 1.6, the urinary peak flow rate increased from 7.7 to 16.3 ml/s, the residual urine volume fell from 151 to 32 ml, and the mean prostate volume declined from 47.4 to 32.2 ml in the first 3 months of follow up; 9.2% of the patients required further treatment within 1 year because of persistent obstruction. The complication rate was low. Statistical analysis showed no factors allowing prediction of the outcome. ILC is an effective method with few side effects and complications, and it has a wide range of indications for all BPH patients.