This article aims to give a broad overview of some of the potential targets for nitric oxide (NO) in the brain. The relevance of NO in both physiological and pathological scenarios is considerable. There is substantial evidence that neurodegenerative conditions such as Alzheimer's disease and Parkinson's disease, involve NO in their pathogenesis. Here we describe a number of cellular components which may be affected by NO, with particular relevance to neurological diseases. As the mitochondrion (in particular the electron transport chain) would appear to be of importance when considering the deleterious effects of NO, this review has a particular emphasis on that organelle. Cellular and mitochondrial antioxidants such as glutathione and ubiquinone are also discussed. In addition, the pivotal role of the astrocyte in both neuroprotection or neurodegeneration are examined.