Wedding RSVP Card Date Wording

Dear Dr. Dave and Dr. Dee,

I am in charge of the wedding invitations for my sister's wedding. I stated "RSVP 10 August 2007," but she wants me to say "RSVP before 10 August 2007" or "RSVP by 10 August 2007."

Signed,

Which is correct?

Dear Which is correct,

Using either, "on or before" or "by" are fine. Using "by" is more traditional.

RSVP can also be R.s.v.p. or R.S.V.P., which is from the French, repondez s'il vous plait meaning please reply.

Instead of RSVP, you can also state, "The favor of a reply is requested by " or "Please respond by..."