The rise of social media has created a new source of friction for couples: what is fair game for sharing with the world?

If one half of a couple is not interested in broadcasting the details of a botched dinner or romantic weekend, Facebook postings or tweets can create irritation, embarrassment, miscommunication and bruised egos.

Some people are insisting that their partners get approval before posting comments and photographs that include them. Couples also are talking through rules as early as the first date.

"There is a standard negotiation that takes place in lots of relationships, but now there are multiple audiences watching," said Lee Rainie, the director of the Pew Research Center's Internet and American Life Project, which explores technology and human behavior. "There will be awkward moments, even more so if that negotiation is played out in public."

Rebecca Gray, a doctoral student at Michigan State in East Lansing, lives with her boyfriend, Ernest Whiting. Last May, Mr. Whiting took a photo of her face slathered in a beauty mask of volcanic mud.

In August, Ms. Gray received a notification from Facebook that she had been tagged in a photo. Mr. Whiting had retrieved the photo from her computer and posted it on his account. "My jaw dropped," she said.

She demanded he take it down. "It was showing up in my newsfeed," Ms. Gray said. "People said: 'What is this? It is hilarious!'" She logged into his account and removed the photo. "I said: 'You have lost the privilege of using my computer. What were you thinking?'" she recalled.

Mr. Whiting said he was just having fun. "I suppose if I thought about it in context, I wouldn't have done it," he said. He is unlikely to do it again. "She asked for photo approval, and I said yes," he added sheepishly.

But even couples steeped in social media are grappling with the new etiquette. Nozlee Samadzadeh and Jarrett Moran have had active online social presences for years. In 2009, they set up a Tumblr account called Needs More Salt to post about their cooking. The couple agreed to review each other's comments before posting. Recently, Ms. Samadzadeh said that she almost posted a comment expressing annoyance at having to make supper because Mr. Moran was home late. Mr. Moran did not know he was supposed to cook and asked her to rewrite the post. "I don't want to be embarrassed," he said.

More often, one partner is more eager to share than the other. Two years ago, Jenny Luu, a skin-care specialist in Washington, D.C., said that she asked her husband, Jason Hamacher, a musician and photographer, to stop posting on Facebook when he was away on business. (She didn't want strangers to know she was home alone.)

Two months ago, Ms. Luu bristled when her husband wrote on Facebook about repairs to the roof of their 100-year-old house.

Ms. Luu worried that their friends would think they were bragging. "I don't want people thinking we have so much money," Ms. Luu said. "I don't want to make people uncomfortable."

For some spouses, the best defense is ignorance.

George Stephanopoulos, the former Clinton White House aide who is now a host on "Good Morning America," a popular daily TV show, said he was named "anchor most likely to be anxious about his wife's tweets" at an ABC News party in January. He is married to the comedian Alexandra Wentworth, who has more than 42,000 Twitter followers.

"I have sort of a simple rule," Mr. Stephanopoulos said, laughing. "Don't ask, don't read."

The New York Times