Pacific Northwest National Laboratory (PNNL) has developed the Captive Carry Health Monitor Unit (HMU) and the Humidity Indicator HMU. Each of these devices provides end users information that can be used to ensure the proper maintenance and performance of the missile. These two efforts have led to the ongoing development and evolution of the next generation Captive Carry HMU and the next generation Humidity Indicator HMU. These next generation efforts are in turn, leading to the future of HMUs. This evolutionary development process inherently allows for direct and indirect impact toward new HMU functionality, operability and performance characteristics by influencing their requirements, testing, communications, data archival, and user interaction. Current designs allow systems to operate in environments outside the limits of typical consumer electronics for up to or exceeding 10 years. These designs are battery powered and typically provided in custom mechanical packages that employ sensors for temperature, shock/vibration, and humidity measurements. The data taken from these sensors is then analyzed onboard using unique algorithms. The algorithms are developed from test data and fielded prototypes. Onboard data analysis provides field users with a simple indication of missile exposure. The HMU provides missile readiness information to the user based on storage and use conditions observed. To continually advance current designs PNNL evaluates the potential for enhancing sensor capabilities by improving performance or power saving features, increasing algorithm and processing abilities, and adding new features. Future work at PNNL includes the utilization of power harvesting, using a defined wireless protocol, and defining a data/information structure. These efforts will lead to improved performance allowing the HMUs to benefit users with direct access to HMUs in the field as well as benefiting those with the ability to make strategic and high-level supply and inventory decisions in real-time.© (2011) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.