Mention the term "homeless" and the image that springs to mind isn't of a teenager. Yet children aged between 12 and 18 make up the largest number affected in a country that shouldn't even have this problem. And while the federal government has committed to halving homelessness by 2020, indications are it's getting worse.

Wearing a grey T-shirt, jeans, runners and with a shoulder bag dangling at his side, Andy French*, 21, could pass for any young local taking a late-night shortcut home through a park in Melbourne's affluent inner-south. But instead of disappearing into one of the warmly lit houses on its fringes, Andy swerves up a track through some high grass to the place he's called home for 16 months.

"This spot was a lucky find," he says, stepping into a clearing in the pitch-blackness. "In other parks I've lived in, if you're sleeping, people think you're dead and they'll call the police." But here, in the weeds and dirt behind some scrawny trees, the softly spoken young man has found precious refuge. Ever since being thrown out of his family home in his teens, he has slept on trains, in disabled toilets and out in the open. Even here at his "lucky find" – an under-maintained park just a short tram ride from the city – Andy spent months curled on the ground beneath a tarpaulin until the kindness of a stranger led to a major renovation. "A gentleman saw me here and came back the next day to give me this old tent," says Andy, clearly still grateful for the gesture. "So this is where I've settled."

Crawling inside his waist-high abode, Andy gives marie claire the grand tour: his mattress (offcuts of thin packing foam); his laundry (a garbage bag containing rain-dampened clothes) and his interior lighting (miniature torch). Although it's usually dry, tonight – to Andy's embarrassment – the tent smells of mouldy wetness. "We had heavy rains," he explains, sheepishly. "You're always at the mercy of the elements." And so much more. Swarming mosquitoes require a daily dousing of OFF! and although nobody prods him to see if he's dead, Andy generally won't eat here, "purely because of the rats". Despite all this, he believes life could be worse. "I could be in India," he says. "People live a lot worse than I do – even in some parts of America."

Even in some parts of Australia.

Given our nation's wealth, our record in tackling homelessness – particularly among the young – is hardly world's best practice. Census figures estimate that, on any given night, 32,444 Australians between the ages of 12 and 24 are homeless; either sleeping rough or

staying in temporary, unstable or substandard accommodation. Some experts say it's closer to 40,000. It's a cringe-inducing social haemorrhage born largely out of family conflict and breakdown, entrenched poverty, substance abuse and government policy failure – particularly in affordable housing. "Homelessness is a national scandal," says Nicole Lawder, CEO of Homelessness Australia. Although a 2008 federal government white paper committed $6.1 billion to the goal of halving homelessness by 2020, Lawder says it's too early to say whether it's a realistic goal since money is only now flowing into programs.

Social workers dealing with young homeless, however, say it's getting worse. "Over the past two years we've seen a surge," says Emma Cassar, CEO of Open Family Australia (OFA), an organisation that focuses solely on assisting the homeless young (aged 12 to 25). While children aged 12 to 18 represent the largest group of all homeless, there's evidence that even younger children are winding up on the streets, including a nine-year-old girl OFA workers encountered last year. Cassar says fallout from the global financial crisis is a major factor in the rising numbers. "When families in the lower socioeconomic group get put under the pump, a lot turn to drugs or alcohol," she says. "Homes become dysfunctional. It can become unsafe for the child, or there's violence in the home and children will choose to leave."

Often, the first step is "couch-surfing" at friends' places, but the transition to sleeping rough generally happens within months. In parks, in squats, on trains, in doorways or living out of cars, young people face a multitude of horrors ranging from malnutrition, mental illness and poor self-esteem to violence, rape, drug and alcohol abuse, prostitution and criminal convictions. Then there's the scorn of a largely judgemental public. For organisations like OFA – which has been providing "assertive outreach" in Sydney and Melbourne for more than 30 years – raising money from the public and corporate donors is a constant challenge. "It's not a sexy cause," says Cassar, adding that OFA is 25 per cent government funded. "All too often, people's view is, 'Get a job! You'll solve your own problems!' But they don't understand the many challenges [young people] have already faced, whether it's family violence, sexual abuse, drugs, alcohol, prostitution. You don't

fix that just by getting a job."

Take the 16-year-old Melbourne schoolgirl who fled home to escape a sexually abusive stepfather. "She was on the street, living in doorways," says Cassar. "She ended up charging $30 and a hamburger for sex. These are stories where you think, 'What happened? Where were all the services? Why did she slip through the cracks?'" In some cases, kids believe they'll be safer taking their chances on the streets with meagre Centrelink payments than they will be at home.

So it was for Stephen Cole*, who was beaten so severely by his father at age 14 he spent two weeks in hospital. Now 18, painfully thin Stephen has spent four harrowing years in and out of refuges, boarding houses and in juvenile detention. (Like thousands of homeless youths, he's amassed a criminal record, ranging from stealing to feed himself to resisting police.) Nowadays, he sleeps in an inner-Sydney park. "The cops rub their knuckles on your chest to wake you up, you know, 'You can't sleep here!'" murmurs Stephen, bitterly. "I've woken up to find my bag's been searched and all my shit's on the ground." Recently, he awoke in terror to find one shoe missing and the other being torn from his foot by a homeless man. "I booted him," says Stephen, close to tears. "But, fuck, it's scary!"

Hours before marie claire met Stephen in Sydney's Belmore Park, OFA outreach worker Son Nguyen found him at nearby Central Station. Nguyen is one of 52 staff who seek out homeless or at-risk young people – often in the most dangerous part of our cities – at all times of the day and night. The primary goal is to get them into stable accommodation and re-engaged with education, but OFA helps with everything from organising medical care to providing food vouchers, toiletries, travel passes, youth camps and leadership programs, court support, vocational opportunities, scholarships and more. Today, though, Nguyen is focused on the next few hours of Stephen's life. "I've got to try to make sure he's got somewhere safe to go tonight," he says.

Like Stephen, Deborah Naylor's* childhood has been a study in suffering. "I was the little tomboy of the family," says Deborah of her early years with a drug-addicted mother in Sydney's inner-west. She carries horrendous memories of being attacked, along with her beloved older brother, Matt*, by their stepfather. "Metal poles, cricket bats..." she says. "We never wanted to be in the house because there were always drugs around. It was really hard being a little kid and not understanding why you'd find these weird things on the floor – bongs, needles. I used to pick them up and put them in the bin."

When she was eight, the Department of Community Services placed Deborah with a foster family. Matt had been sent to live with another family, but soon ran away. "I was really little when I came to the streets, seven or eight," says Matt, now a haunted-looking 23 year old. "To eat, I'd either ask people for money or just hold out until the food vans came around the city." Although he's couch-surfing now, Matt spent much of his youth sleeping on trains. In the process, he amassed $25,500 in fines for travelling without a ticket. Transit police know him so well that, "If they see me on the train, they'll leave me asleep, write out a fine and just leave it on me," Matt says, with a sardonic chuckle. He's also been convicted of shoplifting – in order to eat – 220 times.

Although Deborah fared better in her foster home, she was diagnosed bipolar and schizophrenic, and by the age of 16 she, too, was living on the streets. "For six months all I had was one of those hospital blankets and the clothes on my back," says Deborah, who was constantly propositioned to prostitute herself and once narrowly escaped being raped. "He was like, 'I'll kill you if you scream, I'll kill you if you tell anyone.' Just terrifying."

After Nguyen found them about five years ago, Matt and Deborah attended an OFA youth camp at Port Stephens, NSW, and have slowly been trying to rebuild their lives. Now 20, Deborah lives in shelters and has resumed study with the hope of becoming a social worker. While Matt's criminal record has made gaining employment difficult, Nguyen is working on that, too. Last year, he helped convince a magistrate to wipe Matt's colossal backlog of fines. Matt supplements Centrelink payments by selling The Big Issue on street corners, but is desperate to have "a normal job and a normal life". "I'll do anything," he says. "I'll pick up rubbish. I just don't want to ask people for money for the rest of my life."

Like Nguyen, Melbourne-based outreach worker Wayne Nielsen has never been busier. It's 9.30pm on a Wednesday as he heads out on his "rounds" in St Kilda. For 16 years, Nielsen has patrolled the seedy streets in search of youths in the wretched embrace of poverty, drugs and prostitution. "A lot of my clients are girls and guys about 17 to 25," says Nielsen, 42, as he swings his car into Greeves Street – a dimly lit stretch of misery infamous for street prostitution. "But late at night, when I can get out and drive around the back streets, I'll find the younger kids – the 13s and 14s."

About 18 months ago, Nielsen pulled into Greeves Street and saw a 14-year-old girl – the orphan of junkie parents – being pimped by a man of 50 or 60. "I could tell it was her first night out 'cos she was just shittin'," says Nielsen, whose tough manner and finely tuned street radar are tempered by a tender heart. "Her eyes were looking everywhere 'cos she didn't know what was gonna happen next, but I knew." Nielsen threw his business card in the pimp’s face and approached the girl. "I said, 'Luv, if you wanna come with me, get in the car now. Screw him. You don't have to worry about nothing.' That old pimp was standing there, pointing at himself as if to say, 'I'm here! I'm here!' But where is he when she's in someone's car two kilometres away being beaten and raped? And that's exactly what happened to her that night. She didn't get in the car with me. I saw her down here the next morning and she got raped twice that night."

Lately, Nielsen has noticed a disturbing symptom of the affordable housing crisis. "It's almost impossible to rent an apartment now if you're on Centrelink payments," he says. "It's much easier to spend $500 on a car and live out of that. Honestly, so many young girls are sleeping in cars these days, or in campervans on the side of the road." It’s also opened up a new avenue for predators. "If you've got a van, suddenly you're a pimp," he says. "They’re mobile brothels. I mean...it's a total nightmare."

Over the years, Nielsen has been appalled to see how low humanity can sink. "The youngest boy I've seen working was 11 and the youngest girl was 12," he says. "I've found girls in these back streets naked. They've passed out and scumbags have come along, ripped their clothes off and helped themselves to them all night." While he admits to going home some nights and "crying me eyes out", Nielsen remains driven. "I've had that many kids over the years say, 'Oh Wayne, I really needed you on Saturday night but it was 3 o'clock in the morning and I didn't wanna disturb you,'" he says. "I always tell 'em, 'Look, if you call me in the middle of the night, I get paid double.' That's nonsense, of course – I don't get paid double, but that encourages them to call me any time they need my help."

At 60, outreach worker Richard Tregear has been at it even longer than Nielsen and has seen how the poison of disadvantage leeches from one generation to the next. At an ad-hoc OFA drop-in centre in Footscray, five teenage girls tell marie claire about the effects poverty and family dysfunction have had on their lives. Later, Tregear confides he served as a parole officer for the father of two of the girls, "back 30 years ago when he was 14 – so you're getting generational stuff which has been happening for the last 20 years", he adds. "The Lucky Country is not doing a very good job of breaking that cycle."

A social worker since 1977, Tregear has seen countless young lives crippled by entrenched poverty. "It impacts on everything," he sighs. "It impacts on your education, which is the way out: on your housing – life starts when you get out of bed – and on your personal interactions within family and society. The lack of money is terrible, but with that comes a lack of ideas, a lack of things you can aspire to and a lack of hope."

Unless state and federal governments provide enough affordable housing, Tregear fears his will remain a growth industry. "But it is my dream," he says, "to become redundant for all the right reasons."

Sera Hua* is one OFA client who's thankful Tregear is still around. She was just a little girl when he began working with her struggling single mother in the late '90s. Both of Sera's older brothers were heroin addicts and when her mother died when she was 10, "Richard really helped us a lot," says Sera, now 20. For more than 10 years, OFA helped her maintain stable housing, organised to have her school fees waived and provided her with travel assistance and textbooks. "I couldn't have afforded a bus ticket, let alone school fees," says Sera. After she gained her HSC, Tregear helped her enrol at The Australian Catholic University, where she's now in the final stages of becoming a qualified nurse. "Im just so grateful," says Sera. "When someone offers to help you live a normal life, you have to grab it with both hands."

It's something Andy French ponders during long, lonely hours in his tent. He's acutely aware of what awaits him if he doesn't try. "I see a lot of [homeless] guys who are older than me – I call them dead men walking," he says. "But I look at the task ahead of me and it’s just so daunting.” Wayne Nielsen has been helping Andy with that.

"He's shown me how to break it down into smaller tasks," says Andy. "Yknow, 'First thing you need to look at is some decent accommodation.' If I could get into a TAFE course, for example, I could get cheap accommodation living on campus. So Wayne's helped me apply for TAFE. He's shown me there's a practical way back and I know I've gotta take it – I don't want to be a dead man walking."

To make a donation to Open Family Australia, go to www.openfamily.com.au.