Radiofrequency ablation is an effective tool to treat benign thyroid nodules up to about 100 ml. It is well tolerated and is - together with echopulse therapy - currently the most frequently used technique in Germany for the local therapy of benign thyroid nodules. Overall, a volume reduction of about 50 % to 70 % can be expected. Cystic nodules and mixed-pattern lesions respond slightly better than solid nodules. Initial volume, structure and echogenicity are important parameters influencing the therapeutic efficacy. Bipolar as well as monopolar methods are used - the choice of the method depends mainly on the personal experience. For bigger nodules, the bipolar technique is preferred. Cooled systems should be favored, especially when using larger probes. Serious side effects are rare (< 1 %) and transient in most cases.