They’re always on the lookout for someone.

Last month the missing children came in a pair. They were a couple of friends, 13-year-old girls from Oklahoma who jumped into a parent’s Nissan and disappeared, with nothing between them but $2 and a tank full of gas.

For the families, it must have felt like a lifetime as the hours ticked by, though it was only a matter of days before the girls were found. They’d gone to New York to rendezvous with a 19-year-old man who met them on the Internet and had the sense to turn them in. The moms flew in to pick up their girls, scolded them, and safely escorted them home. It was a storybook ending to a tale that, thankfully, didn’t make its way to the back of a milk carton.

If only they all worked out like that.

“It’s a great story but it’s unusual,” Bruce Henry, executive director of Covenant House New York, said. “The image is a kid ran away Tuesday from the Upper West Side and he gets here. That’s just not how it works.”

Of the 4,300 residents he sees a year at New York’s largest shelter for runaway and homeless youth, Mr. Henry estimates that only 10% fit the stereotype of the misunderstood kid who packs a duffel bag, slams the door, and jumps on the midnight Greyhound. Most of the runaway and homeless youths he sees haven’t laid eyes on their parents in ages. When they show up at the shelter, it’s been a good while since they first stepped out into the cold.

They’ve been bouncing around the homes of relatives, friends’ parents, boyfriends’ or girlfriends’ parents, foster parents, and even strangers. Some pass time at mental institutions, some at prisons.

As the economy picked up in the mid-1990s, the numbers of residents per year at Covenant House dropped some, but today Mr. Henry reports the numbers are creeping up again, reflecting the poverty level that has come to beset 11.2 million American households. He expects more to fetch up as the winter sets in. Recently Congress designated November as National Runaway Prevention Month, hoping to increase awareness and give children access to hot lines and other counseling services to deter them from running away. But it’s not as simple as convincing a kid to take a deep breath and try to get along better with mom and dad.

Most minors who contemplate entering a shelter aren’t turning their backs on functional family lives. “They’re living in a spiral,” Mr. Henry said. “You don’t get here unless you’ve really struggled.”

It’s estimated there are 1.6 million runaway and homeless youths in the country, but since many of the children are living under the radar and not using services that keep figures, there’s no reliable way to keep track.

“When a young girl is on the street, it’s easy to shack up with someone for a couple of months and then move on to stay with someone else,” Carlos Cortes, assistant commissioner for Youth Program Operations with the Department of Youth and Community Development of New York City, said the other day. Mr. Cortes met with a group a few weeks ago to brainstorm methods of keeping count, but he still hasn’t found a survey process that he is convinced will work.

The country has 366 emergency shelters, 192 transitional living programs, and 143 street outreach programs for runaway and homeless youth, according to Mishaela Duran, director of public policy at the National Network for Youth, an advocacy group in Washington. Many, such as Covenant House, run on private donations.

In the 1980s a major force sending children onto the streets was the crack epidemic, which infiltrated hundreds of thousands of households, and turned formerly tame environments into sites of frenzy. Drugs still play a part in the situation, but their presence isn’t as strongly felt.

Nowadays, some youths take their parents or foster parents up on empty threats to “start contributing or get out.” Some leave because their constant disputes with family members make living at home unbearable. But the two greatest themes that Mr. Henry sees are abuse of either a physical or sexual nature and the foster-care system. Many youngsters run away from foster care when they’re still minors. Others find themselves unable to make it on their own when they graduate from foster homes at age 18.

Foster children always make up between 30% and 40% of Covenant House’s population. On a national level, 25% of people who’ve been in foster care go on to experience homelessness. “The real issue is the kid always believes he’s going to be placed somewhere, no matter what happens,” Mr. Henry said.

In 1999 Congress passed the Foster Care Independence Act, also known as the Chafee Act, which doubled the money the federal government provides to state-run independent-living systems for foster youths leaving the system. “That was passed but we’re seeing no differences,” Mr. Henry said. “They’re still ending up here.”

That’s what happened to a 20-year-old resident, who asked to be referred to as Destiny McLean. She sat in a conference room at Covenant House one day last week, twisting her hips in her swivel chair at a rate that would keep a hula-hoop aloft. She spoke at a rapid pace, in a matter-of-fact tone that did little to soften the horror of her tale.

Destiny and three other siblings were placed in foster care when she was 8, after her father’s attempt to cut a cancerous lump out of her mother caused the woman to bleed to death. Destiny and her siblings bounced around a total of five foster homes. “We were wild children,” she said. “We were very aggressive and active.” One of her foster mothers beat the kids up because of their habitual bed-wetting. Destiny eventually left and entered a group home instead.

She’s been living in Covenant House for about six months and says she refuses to lose hope. She’s working part-time as a household helper – it’s like being a babysitter except the mom is still at home – and is studying for her GED. She seemed desperate to make her situation seem as normal and trouble-free as possible. She wanted me to believe in her. “It’s an excellent program here,” she said quickly, in a voice devoid of intonation. “There is no hard part.”

After kids check into Covenant House, they tend to spend about a month in the crisis shelter, where they follow a strict schedule that includes waking up at 6 a.m. and spending the day either looking for a job or training for one. They move into a transitional building in Chelsea, where they pay a nominal rent, $50 every two weeks, that is returned to them when they move on, after 18 months, to living independently. A third of the children who check in leave after the first day, but after that the drop-out rate isn’t high. It’s not until the residents have graduated from the program, and the support system isn’t there, that the real problems hit. “The biggest single place you go from a youth shelter,” Mr. Henry said, “is jail.”

Even Mary (she asked that her real name not be used), a 20-year-old resident who seems set to succeed, fears for her future. A former Alvin Ailey dance student, Mary wasn’t abused or raised in foster homes – she left her mother’s house in Manhattan, she said, simply because she didn’t get along with her mother’s boyfriend. Her situation is far less worrisome than the plight of other residents, yet Mary’s terrified. “I’m afraid I’m going to mess up,” she said in a near-whisper.

It wasn’t until the very end of my conversation with Destiny McLean, the fast-talking optimist, that the young woman decided to tell me she’s three weeks’ pregnant. When she told her coordinator, she said, he responded by saying there was nothing he could do about it and suggested that she consult with a fellow resident, an young expectant mother who is about to move into a shelter for pregnant women. Covenant House has such a unit, but Destiny says other pregnant women told her it has no vacancies.

For now, she says, she can stay put, but once she starts showing she’s going to have to move. Her boyfriend’s offered to let her stay with him at his parents’ house, but she’s wary of such an arrangement. “I don’t want to end up in a situation where I’m in a cycle,” she said proudly. “I got to keep my head up real high and think positive.”

For its part, Covenant House says that Destiny must have misunderstood what her counselor was saying, as the facility’s mother-and-baby unit is never full. “Most certainly she would not have to leave,” Stacy Allison, director of communications and public affairs for Covenant House New York, said yesterday.

A few days earlier, when I asked Destiny how the stress and the uncertainty make her feel, she was quick to explain her situation doesn’t leave much room for feelings. “I never sat back and said, ‘Well, how do I feel about this?’ And I don’t want to,” she said. “I think I’d fall into a depression.”

The whole time, she continued to twist her hips this way and that.