This Element examines visual perception in the context of activities that involve moving about in complex, dynamic environments. A central theme is that the ability of humans and other animals to perceive their surroundings based on vision is profoundly shaped by the need to adaptively regulate locomotion to variations in the environment. As such, important new insights into what and how we perceive can be gleaned by investigating the connection between vision and the control of locomotion. I present an integrated summary of decades of research on the perception of self-motion and object motion based on optic flow, the perception of spatial layout and affordances, and the control strategies for guiding locomotion based on visual information. I also explore important theoretical issues and debates, including the question of whether visual control relies on internal models.