This article highlights the central importance of Pāli phonetics in Theravāda Buddhism. In doing so, I focus on a single yet fundamental point of contention regarding the number of sounds in the Pāli language from the twelfth to fifteenth century. I argue that this debate on the number of sounds was of central concern due to the importance of Pāli pronunciation in the ritual sphere, the development of new regional monastic identities, and the introduction of regional scripts. In tracing this (...) debate between two competing systems of Pāli grammar I show that these developments in the phonetic description of the Pāli language reveal the use and adaptation of Sanskritic phonetics in order to differentiate Pāli from Sanskrit, the Prakrits, and its surrounding vernaculars. (shrink)