Radiofrequency thermal therapy of the prostate is a new minimally invasive treatment for symptomatic benign prostatic hyperplasia (BPH). The procedure is called transurethral needle ablation (TUNA). With TUNA, the inner region of the prostate is selectively ablated with temperatures approaching 90-100 degrees C while the prostatic urothelium is preserved. The objective of this article is to discuss the basics of radiofrequency energy, instrumentation, surgical techniques, and to present an update of the clinical results as it applies to the treatment of BPH.