Despite remarkable progress of diagnostic imaging and operative procedures radiological interventions play a major role in diagnostic and therapeutic liver tumor interventions. Percutaneous biopsies should be taken by 16-20 g needles. CT control is indicated in cases when sonographically guidance is impossible or of risk. MR guidance is still seldom. Accuracy rates of percutaneous biopsies are high (>90%), and safe with complications (e.g. bleeding) of less than 1%. Palliative percutaneous therapeutic interventions of primary or secondary liver malignancies are thermoablative procedures of laser (LITT), cryoablation or radio-frequency, percutaneous ethanol injection (PEI) and intraarterial chemotherapy via port system or repetitive catheterisation with perfusion or embolization (TACE). For metastatic disease with less than five tumors of less than 4 cm LITT and PEI are recommended, more advanced cases should be treated by intra-arterial port system chemotherapy. For HCC best results are shown for PEI, in cases of UICC stage IIIB and IV only TACE is adequate.