Chemotaxonomy is poised to have a major impact on how cannabis is categorized and understood - by both the scientific community and the general public. With a brief review on the historical basis for cannabis taxonomy we will set the stage for a detailed review of cannabis chemotypes and the various models of chemotaxonomy proposed in the scientific literature. We will close with a discussion on what key attributes must be achieved in a cannabis labeling system to convey complex phytochemical and chemotaxonomic information in a simple to understand retail level product label.