Explore the landscape of authentication methods in augmented and virtual reality (AR/VR) environments in this comprehensive IEEE conference talk. Delve into the unique challenges and possibilities presented by AR/VR technologies for user authentication. Examine survey results from users and developers, and learn about the properties used to evaluate authentication methods. Analyze current knowledge-based and token-based authentication approaches in AR/VR applications, including automatic paired accounts. Discover proposed authentication methods, including knowledge-based techniques, physical and behavioral biometrics, and multi-factor solutions. Gain insights into the most promising incumbent methods and future directions for AR/VR authentication, providing a systematic overview of this critical aspect of immersive technology security.