- Never ask a host who else is coming;
- It is impolite to change your mind after you have responded, even if a better offer comes up;
- Respond earlier rather than later;
- Formal invitations to weddings sometimes have an RSVP card that you can complete and post back;
- Often the host will let you know how they want you to respond by leaving their email address or phone number;
- It's rude to ask if you can bring someone unless the invitation specifies 'and guest' or 'and partner.'