Author Gideon Smith is Chief Director: Research and Scientific Services at the South African National Biodiversity Institute, and holds the John Acocks professorial chair at the University of Pretoria. As a past president of the International Organization for Succulent Plant Study, and chairman of the World Flora Project, he also holds various positions on the steering committees of international botanical initiatives. His work on succulents has been widely recognized and he is the recipient of the prestigious Cactus d'Or (Monaco/IOS), a Fellowship from the American Cactus and Succulent Society and the Allen Dyer Medal (South African Succulent Society). He has published numerous books, scientific and popular papers on succulent plants. Consultant Dr Tony Mace has been involved in the management of the British Cactus and Succulent Society for many years and is currently publications manager and webmaster. He and his wife have authored a book on cacti and succulents, and regularly lecture on the subject both nationally and internationally. They have a personal collection of some 5,000 plants which has featured in a number of TV gardening programmes.