While recent years have witnessed a growing interest in Voluntary Task Switching (VTS), the control mechanisms that are required in order to switch tasks on a voluntary basis remain to be identified. Starting from the finding that in VTS the proportion of task repetitions is usually higher than the proportion of task switches ( task-repetition bias), the present electrophysiological study tests and confirms the hypothesis that, during VTS, one initially re-selects the previously executed task, before correcting this bias and selecting the alternative task. On the one hand, these findings allow us to describe how people switch cognitive tasks voluntarily. On the other hand, our approach underlines the usefulness of electrophysiological measures in understanding the processes by which voluntary behavior occurs.