Speech is the primary means through which most people express themselves. However, speech must be sufficiently intelligible to enable successful communication. The estimated 2.5 per 1000 children who have cerebral palsy (CP) are at significant risk for communication disorders. Different speech, language, and communication disorder profiles have been documented in children with CP. However, a common theme across profiles is reduced speech intelligibility relative to typical age expectations. For about half of children with CP, intelligibility deficits can be clearly associated with clinical manifestation of the speech motor disorder dysarthria. Recent work from our laboratory also indicates that many additional children with CP may have sub-clinical speech motor deficits resulting in subtle intelligibility reductions. Reduced intelligibility has significant negative consequences for functional communication, social participation, and quality of life. Enhancing intelligibility is a primary goal of intervention. One critical challenge in children with CP is early diagnosis of speech disorders. A key problem is differentiating those with borderline or mild speech motor deficits from those who are within an age appropriate range of variability. A significant barrier is that systematic age-based performance standards establishing benchmarks and cut-points for typical versus atypical development on variables that reflect functional speech motor performance and are valued outcome measures in dysarthria do not exist. Thus, empirical differentiation of typical from atypical speech motor ability is extremely difficult, especially for children with more subtle deficits (i.e. those with mild dysarthria and those with CP who may have sub-clinical speech motor issues). As a result many children with CP may miss an important window of opportunity for intervention. This research will address the problem of early diagnosis of speech motor disorders in children with CP by 1.) creating growth curves based on empirical data that establish age- specific expectations and quantify the range of typical variability for children between the ages of 3-7 years on measures of functional speech capacity (intelligibility, speech rate, intelligible words per minute) that are known to be problematic in dysarthria but that have never been comprehensively quantified from a developmental perspective in typical children. 2.) establishing standards (via directly measured and statistically validated age-based cut-points) for the identification of typical and atypical functional speech performance. Results will enable early empirical identification of speech motor deficits in children who are at-risk based on their CP diagnosis. The ability to confirm speech motor deficits in the early years and to differentiate the mildest cases from typical developmental variability will ensure that children are identified for treatment, capitalizing on the benefits of neuroplasticity and growth. Furt...