The Label Stacking Options dialog box allows you to control how the stacked lines within the label are justified, what characters will be used to split lines, where the split should occur relative to the stacking characters, and whether or not the stacking characters should be visible in the label.

It also allows you control whether stacking occurs only when space is an issue or whenever a stacking character is encountered in the label.

Finally, it allows you to control the overall shape of the stacked label by specifying the number of lines and the minimum and maximum number of characters per line in the label. The Stacking Separator table shows all of the stacking characters that Maplex will use to split and stack labels.

By default, three characters—a space, a comma, and a hyphen—may be used to split a label. The list of Stacking Separators can be changed by adding to and removing from the table. You can specify for each character in the list whether it will always split a label by checking Forced split.