Definition of Angiosperm phylogeny group

The Angiosperm Phylogeny Group, or APG, refers to two international groups of systematic botanists who came together to try to establish a consensus view of the taxonomy of flowering plants that would reflect new knowledge in angiosperm relationships molecular systematics. Two papers resulted from these collaborations, commonly referenced as 'APG I (1998)' and 'APG II (2003),' and were largely attempts to deal with the deficiencies in prior angiosperm classifications (Cronquist 1981, Thorne 1992 and 2001, Takhtajan 1997) as seen by phylogenetic theories based on analysis of DNA.