A study investigated current and potential uses of the "Primary Language Record" (PLR), an assessment instrument for evaluating and supporting the development of students, particularly in literacy-related areas. The PLR uses focused interviews with students and families, systematically recorded teacher observations, and rating scales of the continuum of progress in literacy learning to inform teachers about students' cultures, languages, past experiences, and interests. In the study, 20 New York City elementary school teachers discussed experiences using the PLR with students of diverse needs and backgrounds, and the utility of specific features for assessing and supporting learning. The study also examined the instrument's impact on aspects of school life, particularly professional development of teachers and student placement decisions. Results are reported through anecdotal information and synthesis. It was found that the PLR supports diversity by providing culturally informed insights into family context and student attitudes, recording direct evidence of individual learning processes, and providing a developmental continuum for learning. Participating teachers credit the PLR with positively influencing their approaches to student learning and their own teaching, changing instructional strategies, and providing previously unnoted evidence of student progress. The instrument is appended. (MSE)