Few scientific topics currently attract as much attention as stem cells. While public debate has focused on embryonic stem cells from animals and humans, stem cells are common to all multicellular organisms. In most animals, the only “true” totipotent stem cell is the fertilised egg and its immediate descendants. Many plant cells, in contrast, continue to be totipotent throughout the plant’s life, and plant stem cells are much more easily obtained and analyzed than those of animals.