The U.S. Army STRICOM is researching technologies to embed advanced simulation and training capabilities in the Objective Force Warrior (OFW) system. The OFW is an individual soldier system of systems approach for mounted, as well as dismounted forces. OFW will be the Advanced Capability upgrade to Land Warrior (LW) which is the Army's first fully integrated infantry fighting system. This paper will describe the research that has begun at STRICOM's Cross Domain Technology (CDT) enterprise to explore mixed reality technologies for dismounted soldier embedded training and simulation. The research is focused on the development and testing of simulation software that exploits rapidly advancing mobile computing platforms, 2D/3D graphics, interactive simulation models, and mixed reality technology. Commercial off the shelf (COTS) hardware, being used as surrogate OFW hardware at the CDT test bed, includes portable/wearable/handheld computing and display devices, video and optical see-through head mounted displays, and position tracking and orientation sensing devices. The Embedded Training (ET) and simulation software being developed by the ETDS Integrated Product Team (IPT) is hosted on these hardware devices. Various advanced simulation software programs and applications are being integrated with the surrogate hardware using augmented reality technology to support mixed live and virtual training and mission rehearsal. In addition to the application of mixed reality concepts - mixing live and virtual simulations - testbed research will address fully virtual embedded capabilities for dismounted soldiers to plan and simulate combat missions while in their barracks, enroute to a mission, or in the field.