Identifying low-progress readers easily and quickly is an essential prerequisite for effective literacy intervention in schools. In this study, teacher judgment of reading performance is compared with a curriculum-based measurement procedure. This study involved 33 teachers and their Year 3 to Year 5 classes. Twelve students were randomly selected from each class and their teachers were asked to rank them based on their judgments of student reading performance. All students were also assessed on a Passage Reading Test (PRT) based on the principles of curriculum-based measurement. The obtained oral reading fluency measures for the students were ranked for each class and compared with teacher judgment rankings. The results indicated that only one-half of the teachers identified the same poorest reader as did the curriculum-based PRT. Moreover, only 15% of the teachers identified the same 3 lowest performing readers as the PRT. These findings suggest that over-reliance on teacher judgment for identifying low-progress readers may be misplaced and that curriculum-based PRTs may provide a more objective and quick alternative procedure.