In my apartment building, I can tell you what the roommates across the hall fight about and that the guy upstairs has a squeaky mattress. What I cannot tell you is any of their names and that, experts say, doesn't do anyone any good.
Neighborly relations have declined in the United States since the 1950s, for reasons sociologists don't quite know, and lack of local ties is bad for crime and a community's ability to organize for their interests, to say nothing of leaving you stranded when you need one more egg.
Some 28 percent of us know none of our neighbors' names, reports a 2010 Pew survey; it's particularly pervasive among younger and lower-income people.
"The biggest barrier is just a perception that we should not be involved," said Keith Hampton, associate professor of communications at Rutgers University. "We fear having people intrude in our lives, but we also have to recognize ... [the] risk in not knowing the people around you."
Knowing your neighbors can help defuse conflicts before they turn ugly.
"If someone leaves their dog out too late barking, then that's Joe -- it's not some random guy you hate," said Bob Borzotta, founder of neighborsfromhell.com, a chat room for people embroiled in neighbor disputes.
Though technology is partly responsible for making neighbors less relevant (it enables people to get social support from afar), it also is helping revive neighbor ties. Several social networking sites are dedicated to connecting neighbors; Hampton's research shows that people who use those technologies are more likely to talk to their neighbors in person and on the phone than those who don't.
One such site is Nextdoor.com, which has more than 1,900 neighborhoods, said co-founder Nirav Tolia. Its purpose is not social but to solve practical problems, like finding a lost dog or organizing a block party. The majority of posts are either recommendation requests (someone seeking a good plumber) or classifieds (trying to sell a couch). There's also an "urgent alerts" feature that sends an emergency note via text message; a neighborhood in Texas used it recently to alert people to tornadoes.
Jon Elliott, 28, joined the Nextdoor group for his neighborhood in Lancaster, Pa., in hopes of creating a sense of community because, he said, "it's hard to go up to someone walking their dog and just start a conversation."
The site proved helpful when a posting about a car break-in spurred a slew of neighbors to respond that their cars also had been broken into, Elliott said. But neighbors also now wave to each other in the street and call one another by name, he added.
That's not to say neighbors should become best friends. It's the weak ties that make a happy neighborhood, Hampton said, so just make it a point to say hello or offer to collect someone's newspapers if they're going out of town.
Respecting boundaries is vital, Borzotta added. Introducing yourself if you're new to the neighborhood, or welcoming a neighbor who has just moved in, is a good way to establish contact, he said.