The planning and performance of neurosurgical procedures in the past have been based solely on the surgeon’s experience and interpretation of 2D imaging studies (CT, MRI). Stereotactic guidance and intraoperative ultrasound have been the only surgical aids for localizing small intraparenchymal lesions. Recently, frameless stereotactic systems for image-guided surgery have been established and have been demonstrated to be safe and useful for intraoperative guidance in open neurosurgery. Various pointer- and microscope-based systems have been developed that allow identification of the surgical field on preoperative CT or MR images. By 3D reconstruction of the patient’s head and comparison of various approaches to the target lesions, surgery can exactly be planned preoperatively. Neuronavigation facilitates minimally invasive approaches to target lesions, placing less strain on the patients and reducing postoperative morbidity. However, certain instances may lead to brain shifting, resulting in inaccuracy. In comparison, real-time imaging studies, e.g. open MRI, demonstrate the actual intraoperative situation. In future, robot-controlled procedures may improve the precision and safeness of certain operative procedures.