For a long time, radiosurgery was limited to the treatment of brain tumours. For this procedure, the patient’s head had to be fixed in a stiff frame in order to prevent any movement during the treatment. This was the only way to apply high doses irradiation to the tumour tissue, while ensuring the healthy, delicate surrounding tissue remained unaffected. Frames are not only uncomfortable for the patient, they also limit the number of angles from which the tumour can be irradiated. The CyberKnife system is the first and only intelligent, robot-controlled, radiosurgical system which, through the combination of image location and computer-controlled robotics, is able to register, follow and compensate for patient movement during the entire treatment. The system is able to accurately target all parts of the body and to irradiate with extreme precision, with deviations of less than one millimetre. This is why it is particularly suitable for the treatment of tumours in and close to the head, in the spine, the lungs, the prostate, pancreas, liver and kidneys. Thanks to the high precision of the CyberKnife system, the use of a head or body frame is not necessary.