The gutter margin is a typographical term used to designate an additional margin added to a page layout to compensate for the part of the paper made unusable by the binding process. In a facing pages layout (Word refers to this type of layout as "mirror margins"), the gutter margin is on the very inside of both pages. It is uncommon to use a gutter margin in a single-sheet layout, although Word allows you to do that. In single-sheet layouts, the gutter margin is typically the area where you might three-hole punch your paper.

To set the gutter margin in Word, you follow these steps:

1. Choose Page Setup from the File menu. Word displays the Page Setup dialog box. (See Figure 1.)



Figure 1. The Page Setup dialog box.

2. Using the Gutter control, indicate how wide you want the gutter margin to be.
3. Click OK.