rsvp's

what is everyone experience with them. does everybody usually send them by the date on the rsvp, or late? and what if people dont send them at all, then what?

I still have about another 4 1/2 weeks until my RSVP date deadline. So far so good but after the Aug 8th (my RSVP date deadline) FI, my parents, FI's parents and I are going to be calling people who did not RSVP.

I remember when my parents sent their RSVP to my dad's best friend's son's wedding, it got lost in the mail so they called my parents. So for those that do not RSVP, I am going to give them the benefit of the doubt and think that they got lost and call them.