The Angiosperm Phylogeny Group APG II (this paper was compiled by Birgitta Bremer, Kåre Bremer, Mark W. Chase, James L. Reveal, Douglas E. Soltis, Pamela S. Soltis, Peter F. Stevens, who were equally responsible and listed here in alphabetic order only, with contributions from Arne A. Anderberg, Michael F. Fay, Peter Goldblatt, Walter S. Judd, Mari Källersjö, Jesper Kårehed, Kathleen A. Kron, Johannes Lundberg, Daniel L. Nickrent, Richard G. Olmstead, Beng Oxelman, J. Chris Pires, James E. Rodman, Paula J. Rudall, Vincent Savolainen, Kenneth J. Sytsma, Michelle van der Bank, Kenneth Wurdack, Jenny Q.-Y. Xiang, Sue Zmarzty (in alphabetic order). 2003. An update for the angiosperm phylogeny group classification for the orders and families of flowering plants: APG II. Botanical Journal of the Linnean Society 141: 399-436. [PDF] [@journal]

A revised and updated classification for the families of the flowering plants is provided. Newly adopted orders include Austrobaileyales, Canellales, Gunnerales, Crossosomatales and Celastrales. Pertinent literature published since the first APG classification is included, such that many additional families are now placed in the phylogenetic scheme. Among these are Hydnoraceae (Piperales), Nartheciaceae (Dioscoreales), Corsiaceae (Liliales), Triuridaceae (Pandanales), Hanguanaceae (Commelinales), Bromeliacae, Mayacaceae and Rapateaceae (all Poales), Barbeuiaceae and Gisekiaceae (both Caryophyllales), Geissolomataceae, Strasburgeriaceae and Vitaceae (unplaced to order, but included in the rosids), Zygophyllaceae (unplaced to order, but included in eurosids I), Bonnetiaceae, Ctenolophonaceae, Elatinaceae, Ixonanthaceae, Lophopyxidaceae, Podostemaceae (Malpighiales), Paracryphiaceae (unplaced in euasterid II), Sladeniaceae, Pentaphylacaceae (Ericales) and Cardiopteridaceae (Aquifoliales). Several major families are recircumscribed. Salicaceae are expanded to include a large part of Flacourtiaceae, including the type genus of that family; another portion of former Flacourtiaceae is assigned to an expanded circumscription of Achariaceae. Euphorbiaceae are restricted to the uniovulate subfamilies; Phyllanthoideae are recognized as Phyllanthaceae and Oldfieldioideae as Picrodendraceae. Scrophulariaceae are recircumscribed to include Buddlejaceae and Myoporaceae and exclude several former members; these are assigned to Calceolariaceae, Orobanchaceae and Plantaginaceae. We expand the use of bracketing families that could be included optionally in broader circumscriptions with other related families; these include Agapanthaceae and Amaryllidaceae in Alliaceae s.l., Agavaceae, Hyacinthaceae and Ruscaceae (among many other Asparagales) in Asparagaceae s.l., Dichapetalaceae in Chrysobalanaceae, Turneraceae in Passifloraceae, Erythroxylaceae in Rhizophoraceae, and Diervillaceae, Dipsacaceae, Linnaeaceae, Morinaceae and Valerianaceae in Caprifoliaceae s.l.