The Client module Workstation Options Font Mapping tab allows you to map named fonts to other named fonts. For example, if you are licensed for the 132-Column font, you may wish to display and print all documents configured to use the default font with the 132-Column font instead. In this case you would map the default font to the 132-Column font.
If your workstation does not have access to fonts used in your system, you may wish to use font mapping to specify an alternate font, rather than having your operating system automatically substitute a font.