As Ozei says above.
Another side note... some modern meters also allow you to automatically trigger your flash(es) via radio when the button on the meter is pressed to take a reading which is rather nice. For example I have the Sekonic l-358 with the rt32 radio unit fitted inside. This is compatible with the pocket wizzard radio triggers, or in my case the phottix/interfit clone of the PW. Works a treat too.