Acourtia consists of two clades, one with species that have scapiform stems and the other with species that have leafy flowering stems. From about 1873 to 1973, Acourtia species were treated as members of Perezia, usually as Perezia sect. Acourtia (D. Don) A. Gray. J. L. Reveal and R. M. King (1973) reestablished Acourtia for the leafy-stemmed North American species, and B. L. Turner (1978) added the scapiform species. Molecular evidence (H. G. Kim et al. 2002) indicated Acourtia is most closely related to Proustia and Trixis and not to Perezia.