Although not the focus of her article, phonological development in young children with speech sound disorders of various types is highly germane to Stoel-Gammon's discussion (this issue) for at least two primary reasons. Most obvious is that typical processes and milestones of phonological development are the standards and benchmarks against which we measure disorder and delay. Factors that impact children without disorders may suggest underlying causes or co-occurring symptoms of speech sound deficits, prognostic indicators of improvement, appropriate remediation strategies or some combination of these. Equally important is the fact that studying children with disorders can help us to verify and, in some cases, even unpack relationships among factors that are so closely interwoven in children who develop their phonologies at the typically very rapid rate that their individual influences cannot be discerned. Childhood Apraxia of Speech (CAS) is a particularly interesting case in point because, while it is universally accepted to be a motor speech disorder, symptoms include deficits in speech perception and often in literacy-related skills as well.