We propose Push-and-Pull Switching, a window switching technique using window overlapping to implicitly define groups. Push-and-Pull Switching enables switching between groups and restacking the focused window to any position to change its group membership. The technique was evaluated in an experiment which found that Push-and-Pull Switching improves switching performance by more than 50% compared to other switching techniques in different scenarios. A longitudinal user study indicates that participants invoked this switching technique 15% of the time on single monitor displays and that they found it easy to understand and use.