The Pull to Top of Stack tool pulls the selected path to the top z-level of the page. In addition to an x-y location on the page, all paths have a z-level, that is, a dimension that tells whether it is above or below other paths. To pull a path to the top of the page simply touch one of its snapping points. If a path is buried beneath several other paths, you can still lock onto it by changing the snapping Header Option Button button so that it’s Snapping to Bottom Path rather than Snapping to Top Path. See Snapping for more information. Here’s an example: