Conversations with those sleeping rough on Melbourne's streets quickly open up a chaotic web of mental illness, family conflict and inevitably drugs.

The causes of homelessness — which costs Victoria an estimated $194 million a year — are complex and confronting.

There's relationship breakdown and chronic unemployment. People are in and out of court, or jail. Following self-destructive bents down rabbit holes.

The mind gets fuzzy. The heart gets weary. There is no family to ask for help. No ID card half the time, to even open the door to something else.

Lisa, 38

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 23 seconds 23 s Lisa was gutted when she lost her job working with severely disabled children ( Jane Cowan )

People-watching is something you have a lot of time for when you're homeless.

"It's better than TV," laughs Lisa.

She remembers when she was in the rushing crowd. She worked in a menswear store in Elizabeth Street. She also did panel beating, painting and plastering.

But the best job she ever had was working with severely disabled children as a mealtime assistant.

"I loved every minute of that job. I used to come out with yoghurt or whatever spat all over me, but I walked out with the biggest sense of achievement. I felt like I'd done something good that day, you know."

She lost the job when a police check turned up her criminal record.

"That gutted me," she says.

Family conflict is what saw the mother of two end up on the streets.

"It's gone from bad to worse to bottomed right out to nothing. I've been robbed, I was raped. I've been assaulted so many times."

She was bitten by a white-tailed spider while sleeping rough and ended up in hospital. But she has her name on a waiting list for housing and hopes this is the home stretch.

Christian, 36

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 37 seconds 37 s Christian is addicted to heroin and lately he has been hearing voices ( Jane Cowan )

Heroin is what gets Christian through.

It muffles the snide remarks from strangers, softens the concrete.

Born with a heart condition, he's had a pacemaker since he was 13. He unzips his jacket to show the scar.

But lately there's been a complication. He's been hearing voices. People are controlling his mind through the pacemaker, he suspects, using certain brands of mobile phone.

"I'll do things that are not me. They've given me convulsions, heart attacks, all sorts of things."

He's been in and out of jail, accused of stealing from three different stores. False allegations, he says.

"After court, with the crime compo, I should be a lot better off, be able to sort something out, get off the streets."

He'll quit the drugs too. He has before. But right now he needs to manage the voices.

Penny, 31

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 36 seconds 36 s Penny's kids found out she was homeless by seeing pictures in the media and online ( Jane Cowan )

Two years ago Penny had a family and a flat in Reservoir.

Now she sleeps on the ground outside Melbourne Central train station and stares into the middle distance.

She knows how people see her, her skin red and angry in a classic presentation of ice addiction.

She doesn't use crystal meth, she says. The worst thing she ever tried.

A recovering heroin addict, yes. A pot smoker, true. But the skin, she says, is an infection she picks at.

"The doctor says that it's self harm because the way I feel on the inside is the way I'm making myself look on the outside. I look like shit because I feel like shit, basically."

The only jobs Penny's ever had were as a teenager, before she became a mother at 17. She worked at Hungry Jack's and in a sandwich bar at the casino.

Then came drug addiction and, well, these days she's grateful to get a smile or a nod or a cup of coffee from a passer-by.

The descent into homelessness came when she and her partner lost custody of their kids. Their parenting payments transferred to her mother while the couple's rent increased. They fell behind and were evicted.

Even the respite of a night in a backpacker's isn't an option if the place requires ID — neither she nor her partner have any.

Of the stereotype that all homeless people are drug addicts, Penny says:

"Wouldn't you use drugs if you were homeless?"

Penny's five children, aged between five and 13, she barely sees. The kids found out she was homeless by seeing pictures in the newspaper and on Facebook.

"My mum thinks we don't want them but the thing is, to be brutally honest, I'm ashamed and embarrassed at my situation."

Glen, 32

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 18 seconds 18 s Glen sleeps rough but has his American bulldog for company ( Jane Cowan )

It's the traffic that does your head in. The street sweepers. Sirens — anything with sirens.

And the light. On the streets it can be darker during the day, with all the night-time fluorescence.

At 32, Glen has never had a lease.

"I've lived in boarding houses a few times but no rental history. It kind of f***s you for references. It's pretty blank."

After growing up in the eastern suburbs, he was staying with friends until they were evicted, becoming homeless themselves. There were a few weeks sleeping in a suburban park. Stints in boarding houses.

By his side is his American bulldog. The animal sometimes ambles into the street to lie in the sun, oblivious to city traffic. He's nine years old, the dog — a year younger than Glen's daughter, who he says no more about.

Today a bong is taking the edge off but Glen's words drip with sarcasm.

"Maybe I should get an investment property," he muses.

He sneers at the idea he's exercising any level of choice.

"Do you do this on purpose? Is it a financial choice or a lifestyle choice? Is it a considered thing? Would you do it? Would you f****** sleep on the footpath? Would you move out of your house?"

Tani, 20, and Matt, 23

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 44 seconds 44 s Matt and Tani fell in love while living on the streets

At 23, Matt has already kicked a heroin habit.

He was shirtless on the streets of Melbourne when Tani, three years his junior, gave him clothes.

She had come to Melbourne via 18 different refuges, here and interstate, but struggles to put into words why she is homeless.

Now the pair are in love. Life on the streets has been like ten years of relationship packed into six months. Raging arguments and nowhere private to have them, all of it.

"We just want a stable roof over our heads," says Matt.