Radiofrequency ablation (RFA) of colorectal liver metastases is frequently reported, but, however, lacks clear criteria for indication and reliable, convincing results with 5-year survival ranging from 17 to 48 %. RFA may be the appropriate treatment modality in approximately 3 to 5 % of all patients suffering from colorectal liver metastases. To date, RFA seems to be limited to no more than three metastases, each smaller than 3 cm. The main indication remains irresectability due to number, site, distribution and/or marginal liver function. Tumours in the vicinity of larger vessels (predominantly branches of portal or hepatic veins) are a case for controversy, since advances in hepatobiliary surgery enable a proportion of patients to undergo resections which would have been declared irresectable until most recently, and the oncological value of a thermoablation is questioned, as a certain amount of temperature is lost due to convective heat sinks. RFA is not a curative alternative to hepatic resection unless small tumours appear during open or laparoscopic procedures in a patient with elevated risk for early recurrence or postoperative morbidity following liver resection. The inclusion of RFA into a holistic system of oncological therapy is mandatory. Early RFA followed by systemic (regional?) chemotherapy can rather be recommended than chemo only, RFA only or first-line chemo with subsequent RFA.