The 23-year-old mother of two was last seen on January 5, 2008 leaving a friend's house in Queanbeyan.

Her bright red Mazda 121 sedan was found two weeks later on January 19, 2008 at the Kanangra Court car park in Reid. Her phone and handbag were missing. There has been no activity relating to her phone or her bank account.

The mystifying elements to this case are that Ms Haworth has a loving and caring family and she has two young dependants, whom she adored.

Her children were three and four at the time, and now teenagers.

From her family's perspective, there was not the slightest suggestion that the young mother had any reason to simply disappear.

It's national missing persons week this week across Australia and Ms Haworth's baffling case is one which has been highlighted in the hope of generating fresh information from the public.

Ms Haworth's Mazda, which is still held by police at its exhibits centre in Mitchell, was thoroughly forensically examined but no details of that examination and what it may have yielded have been shared with her mother, Beth Cassilles.

Having a personal vehicle from which to possibly draw forensic "leads" is unusual among long-term missing persons, most of whom leave precious few exhibits, especially one the size of a car, to examine.

Having tapped into the significant national resources of the federal police forensic facility at Majura, local investigators are not sharing that level of information with the family, with police saying "it is not usual practice ... to share investigative strategies with families".

"They [the police] explained to me along the way that they can't share some things with me because it might jeopardise the investigation," Ms Cassilles said.

"I'd like to know these things. The only thing they've said about the car is that they would like to keep it because it might be part of a murder investigation at some point."

What's equally frustrating for the family is that in the ACT, investigating long-term missing persons is a shared responsibility within a small homicide team. Officers are drawn away to look at fresh murder or homicide cases, or transferred from the ACT's so-called "outcome two" section into roles at the Australian Federal Police's "outcome one".

This revolving door of detectives doesn't help foster investigative continuity or ongoing relationships with the families of long-term missing persons.

Around 12 months ago, Beth Cassilles was aware that a fresh piece of information on her daughter's disappearance had emerged.

"I know there's been some information shared with the police that seems important and I know that it hasn't been investigated yet because there's not the resources available to do it," she said.

"To me, that information is vital and it's like, 'wow, let's do it', but there's not the resources to do it."

Ms Cassilles's frustration with the investigation into her daughter's case bubbled over three years ago when she made an impassioned plea directly to Chief Minister Andrew Barr on ABC radio talkback.

She asked at that time for more police resources to help find her daughter. Mr Barr promised at the time to contact ACT Policing on her behalf.

Detective Superintendent Jamey Bellicanta said that as time goes on "the opportunity to seek additional information, be it forensic information or digital information, is reduced however, advances in technology have provided investigators with updated DNA and on occasions, personal information that have initiated further avenues of inquiry".

"Each individual investigation is undertaken by, for mine, passionate investigators and I want to stress to families of long-term missing persons that their loved ones are not forgotten," he said.

"But sadly in the mire of ongoing and contemporary investigations, on occasions we aren't placing the resources and effort that needs to be placed into these [missing persons] investigations."

Police and Ms Haworth's family have urged anyone with information about the Canberra woman's disappearance to contact Crime Stoppers on 1800 333 000.