TRUE CRIME: The missing women who were never found.

They’re the words no parent, sibling, spouse or child wants to here: “We don’t know where this person is or what happened to them.”

They’re the words the loved ones of more than 38,000 people hear each and every year in Australia. And while most missing persons are found within a short period of time, there are more than 2,000 people in Australia who have been missing for more than three months.

Some of them have been missing for years. Some of them for decades.

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According to Australia’s National Missing Persons Coordination Centre, every missing persons case remains active and open until the missing person is located.

The families of these women still spend every day waiting for their loved ones to return home.

Sarah Anne McMahon

Sarah was a “happy and healthy” 20-year-old when she left her workplace around 5:15pm in Grenmount, West Australia to meet someone.

It was Wednesday, November 8, 2000, and she hasn’t been seen since.

Auburn-haired and green-eyed, Sarah - who would now be aged 37 - was last seen driving her vehicle, a 1986 White Ford Meteor Sedan, registration 7FO-731 east on the Great Eastern Highway, wearing dark jeans, a black turtle neck sweater and a black suede jacket.

Twelve days after she disappeared, her car was found at Swan District Hospital. Her mobile phone was later located on the nearby highway.

An inquest into her disappearance ruled she was murdered, but no killer has ever been named and her body has never been found.

"The circumstances in which Ms McMahon disappeared are sinister," the State Coroner who oversaw the inquest into her suspected death, Alistair Hope, said in 2015.

"I have confidently been able to exclude the possibility that she died by way of natural causes.

"The evidence points overwhelmingly to the proposition that she died by way of unlawful homicide."

Mobile telephone data found Sarah had received four calls the day she went missing,

Two were from a man named Donald Victor Morey. Despite being interviewed by police on several occasions, and providing evidence at the inquest into Sarah's disappearance, he has denied any involvement in the case.

He claimed she was alive, and even told police she had two children, but admitted most of what he had told police was "mumbo jumbo".

Julie Cutler

At 12:30am on June 20 1988, a 22-year-old Julie Cutler left the Parmelia Hilton Hotel in Perth after a staff function.

Two days later, her car was found upside-down in the ocean off Cottesloe Beach, according to WA Today.

The front driver's side window was open, both front doors were unlocked and the rear doors were locked. Forensic tests determined the ignition and headlights of Julie's car had been on when the car entered the water.

Police ruled out the possibility that Julie had taken her own life, as her body would have washed ashore following her car entering the surf.

"Why didn't her shoes, handbag or some other item of property wash up?" Superintendent Ron Carey, who investigated the case, said in an interview for Channel Nine documentary To Catch a Killer.

"I believe she was never in the car... I believe that Julie was murdered and that the body was buried or secreted somewhere else before the car was dumped in the ocean."

LISTEN: What it's like when a loved one goes missing. Loren O'Keeffe shares her story. (Post continues after podcast.)

Making Julie's disappearance more eerie were reports that someone had attempted to "drive her off the road" in the weeks before she vanished.

In late May or early June, Julie rang her father and said a car had followed her so closely it was almost touching her rear bumper for several kilometres as she drove home from work.

She said the car appeared to be trying to force her off the road or force her to pull over. When the car suddenly veered in front of her, Julie was able to swerve around it and speed away to safety.

She reported the incident to police.

A year after she was last seen, a white Hilton uniform blouse - one that was made exclusively for the hotel's staff and in Julie's size - was handed in to police. It was found alongside a pair of black pantyhose in a plastic bag under a restaurant table a five-minute walk from where Julie worked.

Despite extensive inquiries by police and family and comprehensive media coverage, there has been no information regarding her whereabouts.

Some believe Julie's disappearance is linked to the Claremont killings of the 90s.

Revelle Balmain

Revelle Balmain was a "strikingly-beautiful" 22-year-old model and dancer who was working as an escort when she disappeared on Saturday, November 5, 1994.

On the afternoon of her disappearance, she had visited a client in the Sydney suburb Kingsford, and had planned to meet her friend Kate for a drink after the two-hour appointment. At 7:15pm, Revelle rang Kate and said she was about to leave and suggested a place for them to meet.

She never showed up, and was reported missing when she failed to meet her mother the next day in Newcastle.

The 22-year-old's bag, make-up, diary, shoes, credit cards and keys were found scattered around several Kingsford streets. Her client, a man named Gavin Owen Samer, and the escort agency's owners were interviewed by police.

Forensic evidence uncovered in 2008 suggested she had been murdered in the house of belonging to Samer.

Disgraced playboy Mark Coulton - one of Balmain's wealthiest and most infamous clients - once allegedly said that model was "whacked" and was buried "10 feet under" by brothel bosses. He has denied making the claims.

Despite a coronial inquiry suggesting her last client as a suspect, no charges have ever been laid and there is still a $250,000 reward on offer for any information relating to her disappearance or death.

Anyone with information on the disappearances of these women are urged to contact Crimestoppers on 1800 333 000.