The research model used by the NIOSH Division of Safety Research in the development of the Low-Back Atlas (LBA) was described. According to the authors, low back injury is the leading musculoskeletal disorder in the United Sates and back injuries are the most frequent and costly musculoskeletal disorders. The development of the NIOSH LBA of standardized tests and measures was the first step at identifying risk factors for low back injuries and in the development of effective intervention strategies. The initial goal was to provide a reliable, standardized, clinical assessment for use by medical and industrial communities in assessing low back musculoskeletal injuries (LBMI). A list of performance criteria was developed to evaluate and provide a functional description of spinal movement dysfunction based on symptoms and signs. An expert panel of clinicians, researchers, and educators assembled a list of 105 tests procedures. A peer review panel accepted 85 tests and measures and recommended clinical evaluation. The evaluation task was done by grouping related areas into five categories which were then assigned to research sites at universities or clinical centers. The data on more than 250 LBMI patients were collected and analyzed. A final list of 68 acceptable and marginal tests and measures was assembled. Each test and measure was standardized and a clinical study was performed to evaluate the accepted procedures. On the basis of these trials a final list of 19 acceptable and marginal tests and measures was compiled, peer reviewed, and incorporated into the NIOSH LBA of standardized tests and measures.