Two options:
1. Do a mail merge. Start from the Contacts Folder selecting only the
Contacts in that Category.
2. Send a message to multiple recipients. Use the By Category view of your
Contacts Folder to select the Category > Actions > New Message to Contact...
If you want to hide the recipients, you must Cut and Paste from the To:
field to the BCC: filed with this method.

Signature
Russ Valentine
[MVP-Outlook]
> Hello All:
>
[quoted text clipped - 8 lines]
>
> Terry