This study investigated the acquisition of word initial s clusters of 3-5 year old Dutch children with phonological disorders. Within these clusters, sl was produced correctly most often, whereas sn and sx were the more difficult clusters. In cluster reductions, s+obstruent and sl clusters reduction patterns followed the Sonority Sequencing Principle (SSP) by retaining the least sonorous segment; but this is not the case for the sm cluster, where the more sonorous element is retained. The predictions of the factorial typology are supported. Reductions seem explainable through an interaction between sonority and the prosodic head of the cluster. Exceptions are sn and sx, where no consistent reduction patterns are found. As expected, word production of children with phonological disorders is far less target-like than that of typically-developing children. However, the patterns of phonological simplification and reduction of the two groups are surprisingly similar. It can be concluded that language development of children with phonological disorders is delayed rather than deviant. (Contains 1 note and 5 figures.)