In recent years (1980s and 1990s), the use of novel methods for transfer of genes over a wide range oforganisms, leading to the production of transgenic animals and plants, has been recognized as one of the thrust areas of biotechnology. Transfer of genes by conventional methods of animal and plant breeding, is possible over a very narrow range i.e. within a species. Even by non-conventional methods involving tissue or organ culture, genes can be transferred only at the interspecific or intergeneric level. The modern techniques of gene transfer using recombinant DNA technology, however, allow transfer of genes from even bacteria and insects (or even artificially synthesized genes) to higher plants and animals, thus increasing manifold the possibilities of improving animals (e.g. livestock) and plants. The gene transfer methods, their successful use in production of a variety of desirable animals and plants, and the future possibilities of the exploitation of this technology for livestock and crop improvement will be briefly discussed in this section.