The Hennig Society was founded in 1980 with the expressed purpose of promoting the field of Phylogenetic Systematics. Hennig’s idea that groups of organisms, or taxa, should be recognized and formally named only in cases where they are evolutionarily real entities, that is “monophyletic”, at first was controversial. It is now the prevailing approach to modern systematics.

The Society has a strong international character meeting once a year, typically only every other year in North America. The journal Cladistics is the official publication of the Willi Hennig Society comprising a rich mixture of theortical and empirical peer-reviewed contributions to phylogenetic systematics.