Abstract
Phonological chain shifts have been the focus of many theoretical, developmental, and clinical concerns. This paper considers an overlooked property of the problem by focusing on the typological properties of the widely attested 's > θ > f' chain shift involving the processes of Labialization and Dentalization in early phonological development. Findings are reported from a cross-sectional study of 234 children (ages 3 years; 0 months-7;9) with functional (nonorganic) phonological delays. The results reveal some unexpected gaps in the predicted interactions of these processes and are brought to bear on the evaluation of recent optimality theoretic proposals for the characterization of phonological interactions. A developmental modification to the theory is proposed that has the desired effect of precluding certain early-stage grammars. The proposal is further evaluated against the facts of another widely cited developmental chain shift known as the 'puzzle > puddle > pickle' problem (Smith 1973).