Stereotactic radiotherapy is a highly accurate technique was initially developed for performing the radiosurgery of brain tumors in patients for whom it was deemed be too difficult to proceed to classical excision surgery. In this process, a high total dose of radiation is delivered in a single fraction to a well-defined intra-cranial target. The concept of radiotherapy in stereotactic conditions was extended to one or several fractions delivered to small volumes primary tumors/ metastases in extra-cranial sites (Stereotactic Body RadioTherapy [SBRT]). At present, high control rates have been achieved for lung metastases. Similarly, very high local control rates have been reported in bone metastases after stereotactic radiotherapy.