BENIGN PROSTATIC HYPERPLASIA TREATMENT DEVICE AND METHOD A device and method are provided which achieve tissue ablation as well as tissue coagulation substantially simultaneously during the treatment of BPH by utilizing at least two wavelengths of light. The device and m.ethod improve urinary flow and minimize post-treatment blood loss and edema while maintaining a nearly blood-free operating field during treatment by irradiating substantially simultaneously with at least two different wavelengths of light. The present device and method uses optical fibers including in preferred embodiments special side emitting optical fibere to provide a practical, minimally invasive treatment of enlarged prostates. According to the present invention, tissue ablation is affected by having one wavelength that is highly absorbed in the prostatic tissue while another less highly absorbed wavelength coagulates surrounding hyperplasic tissues while maintaining minimal thermal damage to normal tissue, surrounding the hyperplasia, In a preferred embodiment the highly absorbed wavelength is about 1460 nm and the less absorbed by water but with some significant hemoglobin absorption is about 980 nm. This combination aids the patient by reducing blood loss and edema. It can aid the practitioner, especially where imaging is employed, by maintaining a substantially blood-free area during treatment.