Purpose: This study investigated the psychometric properties of 2 oral language measures that are commonly used for diagnostic purposes with school-age children who have language impairments. Method: Two hundred sixteen children with specific language impairment were assessed with the Test of Language Development--Primary, Third Edition (TOLD-P:3; Newcomer & Hammill, 1997) and the Comprehensive Assessment of Spoken Language (CASL; Carrow-Woolfolk, 1999) within a 3-month period. The concurrent and construct validities of these 2 published tests were explored through correlation analysis and principle-component factor analysis. Results: The TOLD-P:3 Spoken Language Quotient and CASL Core Composite scores were found to have an intertest correlation value of r = 0.596 within this sample, and a paired samples "t" test revealed a statistically significant difference between these scores. Principle-component factor analyses revealed a 2-factor structure solution for the TOLD-P:3, whereas data from the CASL supported a single-factor model. Conclusions: Analyses of assessment measure performance data from a sample of school-age children with specific language impairment revealed concurrent validity values and construct validity patterns that differed from those found in the norming samples as cited in examiner manuals. Implications for practice patterns and future research are discussed.