An item set allows you to group items. Using the Item Sets dialog, you can visually manipulate selected sets of items. You can identify and review the items that meet certain selection criteria. You can use color to visualize certain elements. For example, if you want to show all elements marked for late delivery, you can specify a certain color for these elements. You can then query to select just these elements.

If you create an overlay file from a DGN that contains item sets, these items sets are copied into the overlay.

You can create item sets using a text editor or an Excel spreadsheet and then import the created item sets into the Item Sets dialog.