In the past years there has been a significant increase in the treatment of bladder outlet obstruction caused by benign prostatic hyperplasia. Transurethral electroresection of the abundant tissue (TURP) has since the early seventies been the golden standard. The main drawback of a TURP is the relative lack of hemostasis, due to a confined energy and heat distribution around the resection loop. As sufficient tissue needs to be removed to overcome the bladder outlet obstruction, the ideal treatment has to combine both ablative and hemostatic abilities. After 1992, endoscopic laser and 'non laser' treatment modalities have been introduced, that competed with TURP as to clinical outcome. These treatments have in common that a high amounts of energy is delivered to the prostate to remove tissue either indirectly by coagulation necrosis or directly by vaporization. Various in-vitro and clinical studies were performed using different energy sources, such as Nd:YAG and diode laser light in combination with a large variety of delivery devices. Also TURP was included in the evaluation. The in-vitro results provided understanding of the efficiency in energy delivery, the extent of heat induced in the prostatic tissue and possible side-effects, using thermal imaging techniques. Over the last five years clinical data have been collected for various techniques with a follow-up of two years showing the contact techniques to be superior over non-contact and comparable with the outcome of the 'standard' TURP.