When reaching for an object that unexpectedly moves, the hand is ‘magnetically’ drawn toward the object. This occurs even before the subject perceives object motion [1–3], possibly through sub-cortical visuo-motor processes [4]. Whether a similar process exists for the lower limb is open to question. The evolution of a rapid visuo-motor process has obvious advantages for the hand, for example for catching prey, but less obvious advantage for the foot. Rapid visual driving of the foot may even be hazardous because of the need to maintain balance: this is normally maintained during a step by a pre-step predictive throw of the body which is tightly coupled to intended future foot placement [5,6]. Visually driven, mid-step deviations of the foot would upset this coupling and threaten balance. We ask whether the foot, like the hand, is automatically and rapidly driven by vision, and if so whether the process is suppressed by the balance constraint of stepping.