This is a sources sought notice to determine if there are other capable companies for a potential future competitive procurement for engineering services supporting Aegis-Based Defense and THAAD test and evaluation. The work would primarily be performed at the Pacific Missile Range Facility in Kauai, Hawaii, with additional support required at various national test ranges across the U.S. and at Kwajalein Atoll. The government is considering a Cost-Plus Fixed-Fee contract with a five-year period of performance. The required capabilities focus on pre-mission planning, real-time mission support, and complex analysis of auxiliary sensor data (optical, radar, telemetry) for high-profile flight test events. This is a follow-on to an existing sole-source contract with Raytheon.