Related Clues:

• Get back to the host or hostess
• It may consist of regrets
• Letters sometimes preceding a phone no.
• Evite.com request
• "Reply, pls."
• ''Let us know,'' on an invitation (Abbr.)
• ''Let us know,'' initially
• Confirm, in a way
• Regrets, perhaps
• RSVP
• "Let us know," to an invitee
• Say something back
• Answer, shortly
• Heed an RSVP
• SASE contents, perhaps