Aloe vera is one of the most important cultivated medicinal plants and a key component of the floras of Africa, Arabia, and Madagascar. Here, for the first time since the 1960s, is a comprehensive account of all currently accepted aloe taxa in an easy-to-use and accessible format. Organized by habitat and size, entries for more than five hundred species each include descriptions, illustrations, and diagnostic features, accompanied by information on distribution, habitat, and relationship to other Aloe species. This volume is a must-have not only for succulent plant enthusiasts but for all who need a well-illustrated and comprehensive academic reference to the Aloe genus.