Hi TT,

In the mailmerge main document, use Alt+F9 to toggle on the field codes and
add the following formatting switch inside the closing } of the phone number
merge field

\# "(###) ###'-'####"

Use Alt+F9 again to toggle off the field codes, then execute the merge

Please post any further questions or followup to the newsgroups for the
benefit of others who may be interested.  Unsolicited questions forwarded
directly to me will only be answered on a paid consulting basis.

Hope this helps
Doug Robbins - Word MVP