This paper describes Applied Research Associates’ (ARA) recent advances in Soldier augmented reality (AR) technology. Our AR technology, called ARC4, delivers heads-up situational awareness to the dismounted warfighter, enabling non-line-of-sight team coordination in distributed operations. ARC4 combines compact head tracking sensors with advanced pose estimation algorithms, network management software, and an intuitive AR visualization interface to overlay tactical iconic information accurately on the user’s real-world view. The technology supports heads-up navigation, blue-force tracking, target handoff, image sharing, and tagging of features in the environment. It integrates seamlessly with established network protocols (e.g., Cursor-on-Target) and Command and Control software tools (e.g., Nett Warrior, Android Tactical Assault Kit) and interfaces with a wide range of daytime see-through displays and night vision goggles to deliver real-time actionable intelligence, day or night. We describe our pose estimation framework, which fuses inertial data, magnetometer data, GPS, DTED, and digital imagery to provide measurements of the operator’s precise orientation. These measurements leverage mountainous terrain horizon geometry, known landmarks, and sun position, enabling ARC4 to achieve significant improvements in accuracy compared to conventional INS/GPS solutions of similar size, weight, and power. We detail current research and development efforts toward helmet-based and handheld AR systems for operational use cases and describe extensions to immersive training applications.