The acronym RSVP is the initialism of the French phrase répondez s'il vous plaît, which means 'Please respond'. The literal translation of s'il vous plaît is "if it pleases you".
If someone receives an invitation with a request for an RSVP, the polite thing is to respond.
Sometimes, though rarely, you may encounter "RSVP, regrets only", which means that the invitee is to only reply if she is not able to attend. A non-respnose to this specific type of RSVP means that the invitee will be attending the event.
- Read the invitation closely to find out how you should respond to the RSVP.
- Make sure you reply by the requested deadline (ideally, you should respond as soon as possible so as to not make the host wait until the last second).
- Don't come up with your own method of replying-stick to the reply methods which the host has offered (generally this will be by phone call or email for less formal invitations, or by a self-addressed stamped envelope and reply card if it is a more formal affair).
- If you have to cancel or change the number of guests who will be attending, let the host know.
- If you have sent an RSVP stating that you will be attending, you are obligated to go, unless you have a very good reason such as ill health (yours or a family member for whom you have to care), unavoidable professional obligation, or death). When you RSVP it is assumed that you have checked your calendar (personal as well as professional) and have determined that there is nothing that would conflict with your attendance, so just cancelling because your cousin decided to throw a party is bad manners.
- Don't just add additional persons to your RSVP if there is no place on the invitation to indicate the number of guests you will be bringing along. If your children were invited the RSVP would have indicated as such, so don't ask the host if you can bring children. If you happen to have houseguests, don't ask the host if you can bring them along. Simply send your regrets and state the reason why you won't be able to attend. This will give them the opportunity to extend their invitation to your guests if they so desire.