Neurovirology is an interdisciplinary field which represents a melding of clinical neuroscience, virology, immunology, and molecular biology. The main focus of the field is to study viruses capable of infecting the nervous system. In addition to this, the field studies the use of viruses to trace neuroanatomical pathways, for gene therapy, and to eliminate detrimental populations of neural cells. Neurovirology incorporates the related fields of virology, neuroscience, neurology, immunology, and molecular biology. The main focus of the field is to study the molecular and biological basis of virus induced diseases of the nervous system. The field of neurovirology was formed within the past 30 years. It was founded upon the discovery that a large number of viruses are capable of invading and establishing latent infections in nervous tissue. Such viruses have been shown to produce slow, chronic, or progressive nervous system diseases. There are several diagnostic tools which have become invaluable to diagnosing viral infections of the nervous system. In the past, more invasive methods of obtaining samples for diagnosis were needed such as the use of brain biopsy. Now, with the advancement of technology, less invasive means are used more frequently, such as Neuroimaging and the analysis of Cerebrospinal fluid (CSF).New viruses and viral infections of the nervous system will continue to emerge and the field of neurovirology must constantly expand to meet these growing needs. While the interest in researching viruses that infect the nervous system has increased dramatically over the past 40 years.