The circumscription of the Brassicaceae has not changed drastically since de Candolle’s (1821b) classic monograph of the family (as Cruciferae). In a molecular study using the rbcL gene, Rodman et al. (1996) demonstrated that the Brassicaceae and 16 other glucosinolate-producing families formed a monophyletic order, Capparales. More recently, Hall et al. (2002) sampled four chloroplast markers from genera traditionally circumscribed in Brassicaceae and Capparaceae. Their results indicate three monophyletic families ought to be recognized, with the Brassicaceae sister to Cleomaceae (formerly subfamily Cleomoideae of Capparaceae), and these sister to Capparaceae s.str. The family limits recognized herein follows the traditional concept supported by these molecular studies.