It is recognized by the most recent classification of flowering plants, the APG IV system.

[4] It is defined to contain two families: Canellaceae and Winteraceae, which comprise 136 species of fragrant trees and shrubs.

Although the order was defined based on phylogenetic studies, a number of possible synapomorphies have been suggested, relating to the pollen tube, the seeds, the thickness of the integument, and other aspects of the morphology.

Instead the Winteraceae were considered to be a primitive family (due to the structure of the xylem and carpel, a structure which now seems to be derived from xylem and carpels more typical of the angiosperms as a whole).

However, studies starting in 1999, based on molecular phylogeny or morphology, have supported uniting these two families.