This paper describes the history of the development of taxonomies of psychoactive drug use, and discusses the conceptualization of three recent taxonomies: comparing their features, and considering their application in education, treatment, and harm reduction settings. Firstly, the Drugs Wheel was created in 2012, prompted by the emergence of New Psychoactive Substances and rapid developments in their legislative control. It was created in collaboration with health professionals and trainers in the drugs field, people who use drugs, and harm reduction non-government organizations, as a learning tool for NPS. Secondly, by contrast, the Drug Pyramid was an academic creation published in 2016 that aimed to conceptualize the multitude of NPS then being developed at a rate of two per week, as primarily an educational project. Finally, building from limitations identified in the previous two models, the Drugs Venn was created by the authors for the purpose of this paper and in consultation with staff at a drug checking service provider, with the intention of future application in delivery of drug checking consultations. Viewed together, each model addresses objections raised to its predecessor, and in doing so highlights the multi-dimensional nature of taxonomies, and their potential for generation of further hypotheses.