The 1990s were designated the ‘Decade of the Brain’ by U.S. President George H. W. Bush as part of a larger effort involving the Library of Congress, the National Institute of Mental Health, and the National Institutes of Health, “to enhance public awareness of the benefits to be derived from brain research”.This interagency initiative was conducted through a variety of activities. These included publications and programs aimed at introducing members of congress, their staffs, and the general public to cutting-edge research on the brain; thus encouraging public dialog on the ethical, philosophical, and humanistic implications of these emerging discoveries. The 21st century brings with it multiple challenges and opportunities in view of the explosion in information technology, as well as major advances in molecular biology and genetics. Computers in medicine have revolutionised the investigative modalities, as well as diagnosis and treatment paradigms.5 Neuro-imaging, intra-operative neuro-monitoring, neuronavigation, and neuro-modulation are computer-based applications which are now routinely used in standard neurosurgical practice. A 64-slice CT scan with 3D imaging capability is used for vascular reconstructions during aneurysm surgery and for detailed anatomicopathological demonstration for brain tumour surgery.11,12 Functional neuro-imaging is being studied for epilepsy surgery and certain research protocols.13 MRI spectroscopy (metabolic neuro-imaging) is being used to differentiate brain tumours from infections and metastasis.5,11,14 Intraoperative MRI imaging is nowadays being used for rendering maximal safe resection of the brain tumours such as gliomas and pituitary adenomas.15 Neuromodulation with stem cells for neurological functional restoration is currently being utilized for selected patients with spinal cord injury and certain degenerative neurological diseases.16 Although the results are modest, they offer some hope for these debilitated patients; who are otherwise wheel chair bound.11,16 Rehabilitation will assume a crucial role in improving patient quality of life, since stem cell transplantation and neural regeneration would prevent further cell damage. 1,5 In fact, one downside of this could be an upsurge in medico-legal cases due to heightened expectations of treatment and the unpredictable natural course of the disease process. Graphic-interactive cranial surgery comprises of the planning and practice of cranial surgery using instrumentation that reconstructs digital cranial images into a graphic representation of the head and then allows the surgeon to operate by interacting with this graphic rendering. The operating arm system and the medical videoscope are such examples of frameless cranial stereotaxy.17–19 This could lead to a videolibrary demonstrating surgical procedures and techniques which can then be simulated through virtual reality work stations, thus creating a new methodology for training of young consultants in this field.11,20 This will then be translated into real time surgery which will be known as robotic surgery. The use of stereotaxy has opened up the field of neurosurgery to robotics. Robots have been in use for the past 19 years in neurosurgery, but largely remain unknown due to limitations in current robotic systems. The commercial medical robots available in neurosurgery, such as NeuroMate and MKM, remain to be completely adopted by the neurosurgical fraternity. 21 There is a need to develop more integrated systems in which the robots are linked to the imaging and planning software, or directly to the patient anatomy. Robotic biopsy planning facilitates careful preoperative study and optimization of needle trajectory to avoid sulcal vessels, bridging veins, and ventricular penetration.22 The real challenge for the 21st century neurosurgeon will be to assimilate the tremendous advances in neuroscience that have occurred over the last century and then integrate this into the current practice paradigms.5,11 Advances in computer technology should help create large, central databases of neurological ailments which will then provide a reference model for investigation, therapeutics, and further research into the subject.1,4,5,11 Intraoperative image guidance systems provide real-time images, which could increase surgical accuracy. Image guidance navigation in pituitary surgery provides continuous three-dimensional (3D) information regarding anatomical variations of the sphenoid sinus and relationship of tumors to the internal carotid arteries.23 However, the equipment is expensive and requires specific training for the operating room personnel. Stereotactic radiosurgery for primary and metastatic lesions, as well as arteriovenous malformations, can be performed using linear accelerators and refined systems for visualization and guidance.24 They can allow effective and safe treatment of radioresistant neoplasms. 3D-computed tomographic angiography (CTA) using stereo imaging technology allows viewing of multilayer fusion images for neurosurgical procedures in intracranial aneurysms.25 The brain-machine interfaces (BMI) connect machines to the human brain viz. motor neuroprosthetics involves implanting microelectrodes for restoring motor deficits.26The advances in molecular biology and genetics should also change the way a brain tumour, or a degenerative neurological disease, would be treated.11 Genetic microarray would be able to diagnose the type of brain tumour and then suggest relevant molecular targeted therapies. Detection of genetic abnormalities in utero would help the mother to make an informed decision about the future of her pregnancy. Myelomeningocele has been corrected in utero, so-called foetal neurosurgery, although it has been done in an experimental setting. However, its inclusion into routine clinical practice is yet to be accepted worldwide. Infusion of chemotherapeutic agents directly into the tumour bed using nano-technology would be a major advance in this century.11 The applications of nanotechnology in neurosciences include nerve nano-repair, nano-imaging with nano-particles and quantum dots, nano-manipulation of the CNS with surgical nanobots, and nano-neuromodulation with nano-fibres & nano-wires.27,28 The nano-carriers comprise of polymeric nanoparticles, solid lipid nanoparticles, liposomes, micelles, and newer systems, e.g. dendrimers, nano-gels, nano-emulsions and nano-suspensions. These can be effectively transported across various blood-brain-barrier models by endocytosis and/or transcytosis. They have demonstrated early preclinical success in management of brain tumors, HIV encephalopathy, Alzheimer's disease, and acute ischemic stroke.29 Moreover, magnetic nanoparticles (MNPs) conjugated with peptides or antibodies allow direct targeting of the tumor cell surface, and potential disruption of active signaling pathways present in tumor cells.30 Newer strategies permit better delivery of MNPs systemically by direct convection-enhanced delivery to the brain. Direct injection of MNPs into recurrent malignant brain tumors for thermotherapy is being currently explored. The modern-day neurosurgeon, the so called ‘21st century neurosurgeon’, will have to integrate the information technology along with the advances in molecular biology and genetics. 5,31 Surgery is more likely to become minimally invasive until molecular and genetic targeted options provide solutions to major diseases. Clinical neurology will continue to have its own importance in decision making for surgery, however, technology will help refine techniques, achieve precision, and perfection. Neurosurgeons will have to work in conjunction with other specialities including neurologists, psychiatrists, neuro-radiologists, and basic scientists. For example, epilepsy surgery involves close collaboration between neurosurgeons, epileptologists, neuro-psychologists, and psychiatrists. As such, the neurosurgeon will have to be a leader and a task master. They will have to accept responsibility for actions, both their own and the team's, without any arguments.31 They have to be adaptable to suggestions, since treatments for most neurosurgical diseases have become multimodal. They must maintain patience and show perseverance at all times which will help them overcome obstacles in difficult situations. They need to be well versed with computational neurobiology and telemedicine since future consultations and operative surgery will use digital technology. They should have a sound understanding of bioethics and humanity.31 They should have a good knowledge of neuro-anatomy and physiology, and a scientific research based inclination to the subject concerned. Neurologic tumors may involve the brain or spinal cord and are either primary or metastatic. Patients may become increasingly less independent as a re-sult of direct injury of neural structures responsible for motor, sensory, cognitive, and speech functions. The indirect effects of chemotherapy and radiation therapy (RT) add to the functional deficits patients experience. The number of patients involved is quite large. More than 15,000 new cases of primary brain tumor and 4000 new spinal tumors are diagnosed every year (American Cancer Society, 1990). Ap-proximately 2% of all cancer deaths are caused by brain tumors, which account for roughly 11,000 deaths per year (American Cancer Society, 1990). Metastatic lesions from various sites account for 20% to 40% of brain tumors (American Cancer Society, 1990), occur in approximately 15% of cancer pa-tients (Black, 1991), and produce neurologic symp-toms in approximately 85,000 patients each year. Most spinal tumors are extradural and are predomi-nantly metastatic carcinomas, lymphomas, or sarco-mas (Posner and Chernik, 1978). Patients may undergo surgical resection, chemo-therapy, and/or radiation to combat their tumors. It is important to note that significant functional deficits can exist even before treatments. The following signs were noted in 162 patients with cerebral metastases: impaired cognition (77%), hemiparesis (66%), uni-lateral sensory loss (27%), ataxia (24%), and apha-sia (19%) (Caraceni and Martini, 1999a). Spinal cord compression can occur in 5% to 10% of can-cer cases (Barron et al., 1959). Immediate functional consequences can include pain, sensory deficits, mo-tor deficits, neurogenic bowel and bladder, and sex-ual dysfunction. Rehabilitation management of impairments and disabilities is approached in the same manner as in noncancerous neurologic diseases. However, the pathology of the tumor and the anticipated course of disease progression must be considered carefully when developing rehabilitation goals as well as the time frame required to achieve these goals for an in-dividual patient.