The PhyloCode, a code of phylogenetic nomenclature, has been in development since 1997. A preliminary draft will soon be available on the Internet (http://www.ohio.edu/phylocode/), probably by the time of this meeting. It is hoped that many members of the systematics community will examine and comment on it. Changes will undoubtedly be made in response to public input before the code goes into operation several years from now. Phylogenetic nomenclature is designed to name the parts of the tree of life by explicit reference to phylogeny. The PhyloCode will facilitate the naming of clades and promote clear communication about phylogeny. The need for a more efficient system for naming clades has recently become critical because of the dramatic and escalating improvement in our knowledge of phylogeny. The PhyloCode will make it possible to name clades as they are discovered, without changing the names of other clades. It will also allow those who favor monophyletic taxonomy to name the clades they wish to name without being required to name groups they do not accept. The PhyloCode is designed for concurrent use with the ICBN, ICZN, etc. The first edition of the PhyloCode will govern only the naming of clades, but the intent is to add rules governing species names in the future.

Key words: cladistics, nomenclature, PhyloCode, phylogenetic nomenclature, phylogeny