International Organization for Succulent Plant Study
The International Organization for Succulent Plant Study describes itself as a "non-governmental organization promoting the study and conservation of succulent and allied plants and encouraging collaboration among scientists and curators of significant living collections of such plants, professional or amateur." In 1984, it was decided that the Cactaceae Section of the IOS should set up a working party, now called the International Cactaceae Systematics Group, to produce consensus classifications of cacti down to the level of genera. Their system has been used as the basis of subsequent classifications.
