This study examined parent cognitions and parent-infant interaction in terms of their contribution to infant development in the first 12 months. With a sample of 95 mother-infant dyads, results using structural equation modelling confirmed the expected finding that parent-infant interaction mediates the association between parent cognitions and infant development. An unexpected finding was that the direct association between parent cognitions and infant development was stronger than the direct association between parent-infant interaction and infant development. These findings are discussed with regard to the implications for preventative and early intervention models. (Contains 3 tables and 3 figures.)