Here’s how:

1. Click Add a Contact at the bottom of the Messenger window, or click Contacts and select "Add a contact."

2. Enter a Yahoo! ID or Yahoo! Mail address for the contact. If you don’t know the Yahoo! ID or Yahoo! Mail address of the contact, use their email address. They’ll get an email invitation.

3. Then click Next.

4. Select the group you’d like to add this contact to. “Friends” (the default) adds the name to your main Messenger list. Add a message if you like...so they'll know who you are. :o)

5. Click Finish.

Note: The contact is automatically notified and given the option to allow or deny your add request. If the contact denies your request, they won’t appear in your Messenger List.

Note: Oh, if you add a contact to your Messenger List, the contact is also added to your address book! Finally, you can add up to 300 contacts to your Messenger List.