This study was designed to investigate the concurrent validity of the San Diego Quick Assessment as a measure to establish instructional reading level. Criterion variables used were the Metropolitan Achievement Test: Word Knowledge, Reading, and composite score and the Gray Oral Reading Test. An additional concern was to assess the capacity of the San Diego Quick Assessment to predict error patterns of omission, insertion, and reversal, and positional errors of prefix, root, and suffix. Criterion variables used were the Gray Oral Reading Test and the Silent Reading Diagnostic Test. Some of the findings of the study were that Pearson product-moment correlations among the measures used to establish concurrent validity ranged from .66 with the Gray Oral Reading Test and from .76 to .79 with the Metropolitan Achievement Test: Word Knowledge, Reading, and composite score; correlation coefficients among the San Diego Quick Assessment and the measures used to assess error patterns range from .003 to .19; and the correlation coefficients between the Silent Reading Diagnostic Test and the San Diego Quick Assessment to assess positional word errors ranged from -.25 to .27; those obtained between the Gray Oral Reading Test ranged from -.13 to .09. The results of this study indicated that the San Diego Quick Assessment had the capacity to predict instructional reading level. (Author/MKM)