Inhibition of return refers to a bias against attending to and/or detecting visual stimuli at recently attended locations. In the present experiments, Ss were slower to initiate eye movements to previously attended locations. Furthermore, there was more inhibition when a peripheral (exogenous) flash signaled the target, compared with when a central (endogenous) arrow cue was used as an imperative stimulus. That pattern suggests that some of the inhibition is due to processes involved in detecting visual stimuli, and some of the inhibition is related to the movement of the eye. Subsequent experiments showed that the eye-movement component of the inhibition is not object-centered and does not move if the previously attended object moves, although the stimulus-detection component is object-centered. The results have implications for visual attention in general and for the link between overt and covert orienting.