The Advanced Mixed Reality Interfaces Group, led by Alexander Plopski, focuses on the design of and perceptual effects of user interfaces in Mixed Reality. Our work combines aspects of display design, perceptual studies, and Human-Computer Interaction to better understand how users engage with virtual content presented in Mixed Reality, its impact on users, and ways to improve the user experience. Our focus is especially on the application of eye tracking with Optical See-Through Head-Mounted Displays.