Plants within the Cornales usually have four-parted flowers, drupaceous fruits, and inferior to half-inferior gynoecia topped with disc-shaped nectaries.

Under the APG IV system, the Cornales order includes these families:[2] The oldest fossils assigned with confidence to the order are Hironoia fusiformis, described from Coniacian age Japanese coalified fruits, and Suciacarpa starrii described from American permineralized fruits of Campanian age.

The Cornales are highly geographically disjunct and morphologically diverse, which has led to considerable confusion regarding the proper circumscription of the groups within the order and the relationships between them.

[4] Under the Cronquist system, the order comprised the families Cornaceae, Nyssaceae, Garryaceae, and Alangiaceae, and was placed among the Rosidae, but this interpretation is no longer followed.

[6] However, the relationship between these clades is unclear, and as a result of many historical taxonomic interpretations and differing opinions regarding the significance of morphological variations, rankings of taxa within the order are inconsistent.