This research project investigates the question of just how the syntactic structure of a sentence can affect its pronunciation. The project will make coordinated fieldwork investigations of four languages with diverse syntactic properties (Northern Bizkaian Basque, Xitsonga, Luganda, Irish) in which the distribution of tone is known to be particularly revealing of the general role for syntactic constituent structure in determining the pronunciation of sentences. In these languages the location of the left and/or right edges of phrase-sized constituents is indicated by tonal and other phonological phenomena (insertion of tones at phrase edges, lengthening of the penultimate vowel, etc.) Moreover these languages are known to display phonological effects associated with a distinct, larger, clause-level type of constituent. So data from the pronunciation of sentences in these languages can reveal just what types of syntactic phrases or syntactic clauses count as “domains” for phonology. These domain-sensitive phenomena can moreover provide a tool for assessing whether a purely syntax-based theory of phonological domain structure is adequate as a theory of the distribution of these phenomena in a sentence, or whether appeal also has to be made to properly phonological constraints on domain structure, such as those expressing preference for certain rhythmic patterns.