The integration of gene transfer techniques with neuroscience provides new opportunities to study the cellular and molecular aspects of neuron survival, dysfunction, and degeneration. A variety of viral vectors have been used to probe the effects of new gene expression in neurons, glial cells, and progenitor cells. These vectors provide an avenue to deliver genes with potential therapeutic value as shown by neuroprotective effects in animal models subsequent to the transduction of selected cell types. In addition, basic research in this field provides insight into the signalling mechanisms that dictate cell survival and programmed cell death and helps shape future strategies for gene therapy in the central nervous system. New generations of viral vectors will offer improved gene expression and move the field of gene delivery/therapy closer to clinical reality for the prevalent neurodegenerative conditions that include Alzheimer's and Parkinson's.