This article defines the elements of qanat technology in Spain and describes some recent projects which have advanced our understanding. A brief bibliography is provided that exposes some of the confusion surrounding classification, nomenclature, numbers, and distribution of the qanat. Some examples taken from recent fieldwork illustrate the complexities and show how different elements of hydraulic technology are combined. Hydraulic features at Citruénigo (Navarre), Bureta, Bulbuente and Daroca (all Aragón), Madrid, and Toledo(Castile-La Mancha) are all described. Finally, the paper focuses on recent research into dating these features and highlights a recently completed project that dated episodes of construction and maintenance using optically stimulated luminescence (OSL). This technique seems to offer significant potential for future research.