Last updated: before December, 1998
The following formula removes all '-', '(', '(', and ' ' characters from a phone number. E.g. it turns (123) 4567 8987 into 12345678987 This may be necessary if phone numbers have been imported with these unwanted characters.
You can them use Field Format to display the phone number however you want.
Translate(Translate(Translate(Translate(contacts.Phone, '-', ''), ')',
''), '(', ''), ' ', '')