The Cross-Track Infrared Sounder (CrIS) and Advanced Technology Microwave Sounder (ATMS) will together provide retrievals of atmospheric moisture and temperature profiles for the National Polar-orbiting Operational Environmental Satellite System (NPOESS). The first deployment of the CrIMSS system is scheduled in late 2009 on the NPOESS Preparatory Project (NPP) satellite, which is an early instrument risk reduction component of the NPOESS mission. The ATMS has been tested, characterized and delivered to the NPP spacecraft. Instrument bench and Thermal-Vacuum (TVAC) testing for the CrIS Flight Module 1 (FM1) sensor are scheduled fall 2007 and winter 2008. We describe data analyses and results of sensor tests performed for the ATMS and CrIS Engineering Development Unit 3 (EDU3) and FM1 instruments, and the end-to-end plans for on-orbit verification of sensor characteristics and product validation.