As a guest at many weddings over the years, Megan Lane often took a leisurely approach to the four little letters at the bottom of an invitation: RSVP. Calling her delay in answering a "procrastination issue," she says, "I was the guest who meant to get that RSVP done but just never did. Then someone would call and ask, 'Are you coming?' "
Last year everything changed when it was Ms. Lane's turn to be the bride waiting anxiously for friends to RSVP. Although she mailed the invitations two months in advance, 50 people - a quarter of those on the list - did not respond by the deadline. Suddenly she understood the importance of a prompt reply.
"To have to call all these people was awful," says Lane, of Watertown, Mass. "It was embarrassing. Sometimes you'd leave messages, and they never called back. It made it hard to plan. We spent more money than we should have on people who didn't show up."
Ah, the joys of modern manners. Across the country, Lane has plenty of company. Too often, hosts find, guests appear to regard an RSVP as an obligation imposed on them by uptight hosts whose equally uptight caterers have nothing better to do than worry about head counts weeks before they need to.
The problem may be uniquely American. "People in other countries take their invitations very seriously," says Colleen Rickenbacher, an etiquette expert. "They're much better in responding."
Event planners trace part of this "invitation indifference" to a "regrets only" trend that began about 20 years ago. It became fashionable to tell invited guests to respond only if they couldn't come.
"This took a huge part of the response responsibility off of guests," says Joyce Scardina Becker, president of Events of Distinction in San Francisco. "Once people received invitations, if they were attending, they basically forgot about anything other than the date and time of the event."
Ironically, replying has never been easier. Gone are the rigid days when a formal wedding invitation called for a formal reply - on white or cream stationery, please, and in blue or black ink: "Mr. and Mrs. John Doe accept with pleasure your kind invitation for December 18th."
Today printed reply cards coddle guests. Some hosts even give telephone numbers and e-mail addresses. It couldn't be easier, hosts say.
The failure to reply, multiplied by many guests, can cost a host hundreds or even thousands of dollars in wasted meals and caterers' fees. "It is not just a simple matter of pulling up an extra chair and setting another place if guests show up when they didn't respond," says Judy Allen, an event planner.
Such lapses in etiquette can even affect relationships long after an event is over. Lane and a friend haven't spoken since the friend, after saying she would attend Lane's wedding, never came and never offered an explanation. "To this day I haven't gotten an apology," Lane says.
Apologies were also lacking when Ms. Bennett called many guests who didn't RSVP for her wedding last year. About half were planning to attend and half were not. To her surprise, no one said, "I'm sorry I didn't get a chance to respond."
Some delinquent RSVPers insist their silence is not intentional. "People are overwhelmed by their own schedules, especially single people, and often time slips by," says Lauree Ostrofsky, who was married last month. "Something you thought was weekends away is actually in two days."
Other recipients may not understand their obligation. "Few people take French in high school anymore, and few parents school their kids in simple etiquette," says Patricia Sirek of West St. Paul, Minn. "Some think that RSVP means 'call if you can't come.' Few seem to know that it means 'répondez s'il vous plaît,' 'please respond.' "
Some partygoers even adapt that timeworn excuse of students - the dog ate my homework - claiming the post office lost their invitations.
When Bill McCloskey's family began calling those who hadn't RSVPed for his daughter's wedding, many said they never received the invitation. "We blamed the post office for losing about 10 percent of the mailing," says Mr. McCloskey, of Bethesda, Md. "I don't really know if they did lose them or if people were embarrassed to say they got them and had ignored them."
For social gatherings other than weddings, some hosts take a modern approach. When Kim Sundy and her husband give parties in their Minneapolis home, they usually send invitations by e-mail. "You get a better response," she says. "People can deal with it right away. There's no fumbling around with a paper invitation."
Next year, Mrs. Sundy also plans to use e-mail for her young son's birthday party. Last month she struggled with whether to call his classmates to see if they were planning to attend. "You don't want to appear needy or overbearing, but you also don't want to be so timid that you plan a party no one attends," she says.
Electronic sites such as Evite, an online invitation service, make the process even easier. Guests simply click to accept or decline.
Weary of guests who don't respond, some hosts are taking radical steps. Jonathan Adkins, a communications director in Washington, has adopted a new rule: "No RSVP means that person isn't invited next time."
Robin Schudmak takes another approach. As a frequent user of Evite, which tells a host how recently a guest has viewed an invitation, she phones laggard responders to say she is aware that they've been reviewing the invitation, and asks for a prompt reply.
Ms. Sirek is considering a hard-line approach: "When I issue invitations in the future, I'll write, 'Please respond by [date], or I won't purchase any food for you.' " Last month she spent two hours tracking down those who didn't RSVP for a baby shower her sister-in-law was hosting for her daughter. The invitations went out a month in advance, but half of the 35 guests didn't reply. Only one planned not to attend.
She faced a similar challenge before her daughter's wedding. "One person actually said, 'Well, my caterer only needed a count three days before my daughter's wedding. Why do you need to know so early?' Then she proceeded to hem and haw over whether or not she could or would attend."
No wonder a failure to RSVP ranks No. 1 on the Top 10 list of social faux pas compiled by Leah Ingram, author of "The Everything Etiquette Book."
Etiquette experts urge guests to read an invitation carefully when it arrives. Note the response date and mark it on a calendar. Mrs. Rickenbacher encourages recipients to respond within a week. "The person planning this event needs to continue to make plans," she says.
But what happens if a guest's plans change?
If, after accepting, you find you cannot attend, Rickenbacher says, tell the host, "I'm so sorry, something has come up and I now have to decline the invitation." Or if you declined but now can accept, you can go back and say, "If there's space available, I would like to attend."
If you honestly forgot to respond, and it's two days before the event, Rickenbacher continues, just be honest. "Say, 'It got buried in a stack of things on my desk. Is it too late?' Or if the event has already passed, send a handwritten note apologizing, saying that you misplaced the invitation but you would love to have been there." For a birthday party or a wedding, you can still send a gift.
Rickenbacher is optimistic that the social scene will improve. "Etiquette is starting to come back," she says.
Just ask Lane. After being on the receiving end of friends' failure to respond, she has become the model guest. "I'm usually the first person to reply now," she says.
Even those who don't know French could follow her lead by simply assigning English equivalents to the letters RSVP: Respond So Very Promptly.