The last comprehensive revision of the family was published in 1993 by John Brandbyge as part of "The Families and Genera of Vascular Plants". Brandbyge followed earlier systems of plant classification in dividing Polygonaceae into two subfamilies, Eriogonoideae and Polygonoideae. Since 1993, the circumscriptions of these two subfamilies have been changed in light of phylogenetic studies of DNA sequences. Genera related to "Coccoloba" and "Triplaris" were moved from Polygonoideae to Eriogonoideae. The genus "Symmeria" does not belong to either of these subfamilies because it is sister to the rest of the family. "Afrobrunnichia" might constitute a new subfamily as well.