Sarcoidosis is an idiopathic granulomatous disease affecting multiple organs. Neurosarcoidosis, involving the central and/or peripheral nervous systems, is a relatively rare form of sarcoidosis. Its clinical manifestations include cranial neuropathies, meningitis, neuroendocrinological dysfunction, hydrocephalus, seizures, neuropsychiatric symptoms, myelopathy and neuropathies. The diagnosis is problematic, especially when occurring as an isolated form without other organ involvement. Distinguishing neurosarcoidosis from other granulomatous diseases and multiple sclerosis is especially important. Although biopsy of neural tissue is the gold standard for the diagnosis of neurosarcoidosis, this is often not practical and the diagnosis must be inferred though other tests, often coupled with biopsy of extraneural organs. Corticosteroids and other immuno-suppressants are frequently used for the treatment of neurosarcoidosis. This article reviews the epidemiology, pathogenesis, pathology, clinical features, diagnosis, diagnostic tests, diagnostic criteria, and therapy of neurosarcoidosis.