Notes from a diary kept on the language acquisition of a child from age 11 to 22 months, through four developmental stages, were used to investigate the interaction between the child's phonological systems and his developing syntactic system in the context of research on the emergence of multiword combinations. The presence of a phonological selection strategy and consonant harmony rule was discovered, with evidence that this consonant harmony rule operated across morpheme boundaries with the effect of both delaying the onset of two-word utterances and influencing the selection of words that could occur in combinations. The study provides an explicit example of the role that word-level articulatory planning may play in constraining the occurrence and nature of word combinations. The child's transition from single- to two-word utterance is a struggle to work within and overcome his consonant harmony rules. It is not likely that this is a typical or common pattern, since few similar reports are available in the literature. However, this and other research may help to clarify the notion of language learning styles. (MSE)