The past few years have witnessed extraordinary advances in molecular genetic techniques and the accumulation of structural genomics information and resources in both human and model organisms. With the development of new technologies and the availability of resources like the sequence of eukaryotic genomes, problems of a previously unthinkable scope are now being routinely solved in neuroscience and many other areas of biomedical research. The results of these studies, in turn, are having, and will continue to have, profound impact on experimental approaches and designs for manipulating genes, the genome, and model organisms as a means of gaining insights into nervous system functioning and complex behavior.