Lippa, Nelson, and Toman are recognized for the development of rigorous analytical methods and data-evaluation processes for the determination of chemical purity, and for transfer of this technology to the private sector for the development of a new class of primary Standard Reference Materials. Knowledge of chemical purity is essential for accurate amount-of-substance measurements and for establishing the metrological traceability of these results to the International System of Units (SI). The team’s processes are applicable to a range of NIST’s measurement services, with applications that extend from healthcare delivery to forensic purity assessment of seized drugs.