The Ground Unmanned Support Surrogate (GUSS) was developed by NSWC Dahlgren, Virginia Tech, and TORC Technologies as an autonomous squad support ground vehicle for the Marine Corps Warfighting Lab (MCWL). GUSS is intended to test the ability of autonomous ground vehicle technology to provide Marine rifle squads with an organic transport, resupply, casualty evacuation, and RISTA capability. The primary operational mode is a follow-me capability in which the GUSS navigates autonomously across unstructured terrain to keep pace with an operator carrying a handheld operator control unit. Other modes of operation include resupply missions using a map-based planner, point-and-click local navigation, RISTA missions using teleoperation, as well as an optional manned operation capability. To test the GUSS capability, four vehicles participated in the MCWL Limited Objective Experiment Four (LOE-4) in conjunction with RIMPAC 2010 at the Marine Corps Training Area Bellows in Hawaii. Marine operators were trained to operate the system and the vehicles were turned over to a Marine platoon for four days of simulated field operations. An overview of the development and capabilities of the GUSS system will be provided followed by a discussion of the operational experiences, lessons learned, and future development plans.