We don't! It seems that the confidentiality 'promised' by some web sites shouldn't really be given. Before submitting a C.V. to us you must decide what information to include - anyone will be able to see it. You can 'hide' some additional information behind a password protected 'door' which you can also use (link here for an example) to include a presentation or an example of your recent work - even a video or sound file! Be careful about including anything which you consider to be very private though, we read recently that unscrupulous headhunters are now using a 'robot' to gain access to the C.V.'s held on the server of their competing companies!