Vision plays a central role in the planning and execution of goal-directed actions by informing the actor about the pertinent physical characteristics of the target object. When reaching for a stationary target, for instance, we look at its location and physical properties (size, orientation, shape, etc.) before initiating our movement. If the object is moving, we follow its trajectory visually to anticipate where and when to intercept it. Children and adults who are experienced at reaching and have acquired good control of their arms and posture can easily take advantage of such visual information to tailor their actions effectively to the physical world. But infants who have limited knowledge about the physical world and little control of their body and limbs need to learn how ...