The team is recognized for fundamentally advancing vitamin D metrology by improving the quality and comparability of measurements for the assessment of vitamin D nutritional status worldwide. The team developed, implemented, and disseminated reference measurements and methods, Standard Reference Materials, and quality assurance to support the Vitamin D Standardization Program (VDSP) in collaboration with the National Institutes of Health, Office of Dietary Supplements (NIH-ODS). These efforts provide a foundation to guide public health policies and clinical practice nationally and internationally.