The overall objective of the NPOESS Preparatory Project (NPP)/National Polar-Orbiting Operational Environmental Satellite System (NPOESS) Joint Government Shared System Performance Responsibility (SSPR) Contractor Calibration Validation (CalVal) Program is to ensure the environmental data products meet the system specification, and satisfy the users and scientific community. Work spans all program phases, from pre-launch sensor characterization and data prduct verification to on-orbit calibration verification/data product validation and long-term data product quality monitoring/maintenance. A cooperative approach is in place to leverage expertisxe throughout the program-developer, government-customer and users, and scientific community. Draft Calibration and Validation Plans are in development and NPP pre-launch activities are under way. This paper provides an NPP/NPOESS Cal Val Program system perspective, describes the cooperative strategy, and summarizes progress and planned activities to ensure a successful NPP mission.