After a review was made of the literature related to early identification of reading problems, a battery of diagnostic tests was constructed of receptive and expressive language elements assumed necessary for success in reading. After pilot work and revisions, the battery (PDQ) was administered to 916 entering kindergarten pupils by their teachers, in individual sessions. After testing, follow-up workshops were held with kindergarten teachers to provide suggestions for individualization based on the test results. The effect of the program was evaluated by comparing reading test scores at the end of first grade with those from a comparable population of first graders in the previous year who had not had the kindergarten testing program. Results indicated a significant difference in mean reading achievement in favor of the experimental group. (AA)