Valid assessment of diet and physical activity is uniquely challenging, requiring specialized scientific expertise, creativity and high levels of staff training. The purpose of CANHR's Nutrition and Physical Activity (NPA) Core is to facilitate interdisciplinary research requiring dietary and/or physical activity assessment and intervention. The NPA Core supports all aspects of dietary and physical activity assessment, including selecting and/or modifying appropriate assessment methods, developing quality control procedures, and guiding the analysis and interpretation of the resulting data. We have trained a cadre of investigators, staff, and students to collect and process diet intake data. We will continue providing these services and, as CANHR is moving from observational to intervention research, we propose to expand our services to include developing nutrition and physical activity education materials to support intervention science. The unique and critically important aspect of the NPA Core is its role in adapting the content, design and administration of dietary and physical assessment tools for use in Alaska Native communities. Standard approaches to nutrition and physical activity assessment lack relevance and validity within the culturally and geographically unique Alaska Native context. Continued support for a stable NPA Core will result in an accelerated and long-term growth of nutrition and physical activity research in CANHR and sustainability of this important core resource. Wthin this context, the specific aims of the NPA Core are: Specific Aim 1. To provide and support valid and culturally appropriate state-of-the-art dietary and physical activity assessment methods. Specific Aim 2. To develop and provide culturally appropriate nutrition and physical activity education materials in support of nutrition and physical activity intervention science. Specific Aim 3. To train CANHR investigators and staff in the usage of Nutrition and Physical Activity Core resources.