Neurons are lost from the brain in neurodegenerative diseases like Alzheimer's and Parkinson's disease. The use of Neural Stem Cells (NSC) to replace the lost cells in the damaged brain is an exciting possibility, but our poor understanding of Sociology holds the development of Ness as potential therapeutic agents back. Here, we address crucial questions that need to be answered if stem cell therapy is to succeed. We have identified genes important for NSCs and defined stem cell populations that differ in their capacity to repair. The skills in abroad range of experimental techniques are well developed in the seven participating laboratories. Our approach is to apply this interdisciplinary expertise to clarify the significance of these genes and cell populations in Scraper. We expect to have established some of the basic parameters that determine the success of NSC transplantation as a therapy for neurodegenerative disease.