The rapid development of consumer-grade augmented- (AR) and virtual-reality (VR) devices has created interest in leveraging these technologies across a wide range of medical applications including rehabilitation, image-guided surgery, and diagnostics. In this presentation, we will provide an overview of current AR/VR medical devices and applications in the medical space. We will discuss some of the evaluation challenges for AR/VR devices in medicine and provide summary of the Medical Extended Reality (MXR) research program in the Office of Science and Engineering Laboratories (OSEL) in CDRH. Finally, we will highlight the ongoing regulatory science research in the MXR program to address the current evaluation gaps and challenges.