Gestures are a topic of increasing interest in authentication, but successfully implementing them as a security layer requires reliable gesture recognition. So far, much work focuses on new ways to recognize gestures, leaving discussion on the viability of recognition in an authentication scheme to the background. It's as yet unclear how gesture recognition should be deployed for practical and robust real-world authentication. In this article, the authors analyze the effectiveness of different approaches to recognizing gestures and the potential for use in secure gesture-based authentication systems. This article is part of a special issue on privacy and security.