Background: Research has shown that early identification of children with language issues is critical for effective intervention, and yet many children are not identified until school age. The use of parent-completed rating scales, especially in urban, minority populations, might improve early identification if parent ratings are found to be reliable and valid. Aims: To evaluate the reliability and validity of the Observational Rating Scale (ORS) in an urban setting where it may be difficult to distinguish language difficulties from cultural language differences. Methods & Procedures: The present study examined the degree to which parent and teacher ORS scores for 73 7-10-year-old children (47 boys) had concordance for the four ORS dimensions of Listening, Speaking, Reading, and Writing, as well as for a composite ORS score. The relationship between the ORS ratings and the children's scores on the CELF-3, or CELF-4 Receptive and Expressive scores, and the WIAT Reading Composite scores were also examined. Outcomes & Results: Parent and teacher concordance rates for the ORS were significant, but moderate for the Speaking, Reading, and Writing categories and for the overall ORS score. There were also significant relationships between the ORS scores and performance on standardized language and reading tests supporting the validity of the ORS. Conclusions: The reliability and validity of the ORS have been replicated and extended to a diverse, urban population. Further, parent ratings were shown to provide as least as good information about language function as teacher ratings. Finally, it was suggested that an overall ORS score may provide a better indicator of overall language function than the domain scores. (Contains 4 tables.)