As Victoria's Health Services Commissioner, Wilson is the patients' advocate. From investigating major blunders and abuses to hearing grumbles about doctors' bedside manner, she is both investigator and mediator in complex, often emotionally fraught situations where the facts are frequently contested. It's a delicate balancing act between protecting patients and defending the integrity of the healthcare system. For Wilson, 62, a passionate social justice campaigner with an ebullient personality and a gift for conciliation, the job is a perfect fit. As she prepares to step down at the end of this year after three terms, admirers say her longevity - most commissioners are appointed for one or two terms - is testament to her high standing within healthcare and government circles. In a job where the human touch is so important, her eccentricities - a wicked laugh, a colourful wardrobe, and a love for the mandolin, guitar, harmonica and singing - are applauded as much as her professionalism. She leaves the job with perhaps her biggest legacy - a national ''negative licensing'' scheme to regulate the booming alternative medicine industry - likely to become enshrined in law. Although the timeline is yet unclear, state and territory health ministers have agreed in principle, after intense lobbying from Wilson, to introduce laws to protect the public from unscrupulous providers promising miracle cures for all manner of ailments and diseases.

Unlike mainstream healthcare practitioners, who can be disciplined or struck off by state medical boards if they breach their professional codes of conduct, complementary practitioners are not subject to the same scrutiny. It's a situation Wilson says has led to a burgeoning market for ''shonks selling snake oil''. In her remaining time in the role, she's been asked by Victorian Health Minister David Davis to oversee a reform process she hopes will give her office greater powers to hold dodgy practitioners to account. One of the worst abuses she has investigated was the 2009 case of Melbourne plumber Peter de Angelis who said he was a Sioux Lakota Indian shaman called ''Thunder Eagle'' and claimed he could cure breast cancer through ''psychic surgery''. Six women, some desperately ill, complained to Wilson's office that he had inappropriate sexual contact with them during ''healing'' sessions, often dancing naked in front of them and making them drink their own urine. Wilson was so horrified by the case that she won a Supreme Court battle to name him in the Victorian Parliament on grounds he posed a danger to the public - powers her office had never instituted before. It followed a year-long investigation. She hopes reform will grant her office the ability to name offenders earlier if there are reasonable grounds to believe they are a serial public risk. In a tragic epilogue to a tawdry tale, de Angelis took his own life after he was named. Wilson says that while she felt compassion for him, she would not have handled the case differently. ''He knew what he was doing was wrong. I got a very good psychiatric opinion, I made sure before I named him that he didn't have a mental illness and I'm satisfied that we did it very professionally. He continued to offend while we were investigating. He was acquiring new victims right up to the end.''

Another high-profile investigation was into deregistered dentist Noel Campbell. Wilson wrote a damning report on him in 2008, finding that he had preyed on dying cancer patients and failed to inform them there was no scientific evidence for the treatments he provided, including ozone therapy and electrotherapy. Consumer Affairs Victoria took the case to the Supreme Court, which found that although Campbell's website Operation Smile did not have the support of conventional science, its statements were not misleading or deceptive. However, last week the Victorian Court of Appeal overturned the decision. Wilson, who had pursued the case for four years, burst into tears when she heard the news. Standing up for the little people has been a life-long passion for Wilson, who was raised by a ''strong, grounded'' single mother (her father left to be with her mother's best friend) as one of five kids in a weatherboard cottage in Hastings. From an early age, she loved learning and was a constant questioner. As one of her teachers observed wryly: ''Wilson, you've been vaccinated with a gramophone needle.'' But she grew tired of turning up to class with holes in her shoes and at 15 quit school to earn money in a string of jobs in a chicken factory, fruit picking and waitressing. It was a move she regretted, later going to night school in her early 20s to get her high school certificate before taking up an arts-law degree at Monash University. There, at the age of 22, she found herself unexpectedly pregnant to a boyfriend who didn't want children. After much agonising she decided to have a termination. It was a pivotal moment that would inform her impassioned support for abortion law reform during the 2007 Victorian Parliament debate that led to abortion being removed from the state's Crimes Act.

''I went out to bat for that in a big way because it's a woman's health right and I was very upset by it being turned into a political football. I grew up in a period where women were having illegal abortions, turning up to hospital with horrendous infections. Girls were taking brandy and a boiling hot bath or little green pills, which were very strong laxatives. It was very important that abortion come off the criminal records because it always put a woman or a doctor at risk of being charged. That was just moral cowardice on the part of society.'' Although hard to believe for a woman who, by her own admission, is rarely quiet, she started her career in the late '70s as a librarian, before working through the '80s and '90s as a legal member for a range of organisations that were designed to protect the rights of the mentally ill or socially disadvantaged, including the Mental Health Review Board and the Social Security Appeals Tribunal. A fervent women's rights advocate, early in her career she joined a professional body called Feminist Lawyers, which fought for sexual equality for both clients and those who represented them. One of her proudest achievements was a 1980s battle to free two sisters who were jailed for perjury after reporting their father for incest against his grandchildren but then retracting the claims after intense pressure from the family and his lawyers. ''A psychologist from the prison service contacted us at Feminist Lawyers and said, these girls are not perpetrators, they are victims. We all thought, this is outrageous, what are they going to do about it? And we suddenly realised, it's not they any more, it's what are we going to do about it?'' A campaign was launched and after six months in jail the women were released and pardoned. To free them, Wilson enlisted the help of a high-profile male barrister, learning how to use her softer side while still upholding her feminist ideals - a trait that has served her well as Health Services Commissioner where ''a lot of your time is spent trying to hose down guys who are fighting''.

Former Australian Medical Association president Dr Mukesh Haikerwal says Wilson's departure from the job is a ''massive loss'' to the Victorian health system. ''She's very good at listening to the patient's point of view and being able to mitigate potentially significant escalation by entering the conversation early, listening to both sides and actually understanding why something might have been said or misinterpreted, because the biggest problem in this space is lack of communication rather than necessarily anything premeditated or dangerous.'' Although she's never had children, Wilson has no regrets, enjoying a close relationship with her nieces and a happy marriage to her husband, Dave Mercer, an associate professor of environmental science at RMIT, who has been her partner since university days, though they didn't marry until 1999. She admires ''super women'' who can juggle demanding careers with raising families, and often wonders if she'd have enjoyed the same professional success if she'd had children. When she steps down she hopes to keep working, possibly running health workshops, and spend more time indulging her love of writing. Asked what her legacy will be, she says she's proud of the work she's done to improve healthcare access for those with disabilities and from culturally and linguistically diverse communities. She envisages one of the biggest challenges for her successor will be ethical issues around end-of-life care as the population ages. One of her greatest concerns is the rising popularity of cosmetic surgery. She's seen many patients scarred by botched operations and is angry some surgeons carry out unnecessary procedures on people with serious body image issues. ''I worry like mad about the way some of them are drumming up markets. 'Had a baby? Bit worried about the lower region? We can fix that up for you.' Persuading women that they've got something wrong with them when they don't - vaginal rejuvenation and labiaplasty surgery. Unfortunately, sometimes they end up with terrible results, incontinence, pain, loss of ability to have sexual relationships. We're seeing more complaints about that every year. It's making women hate their own bodies.''

In September last year, Wilson was forced to confront her own body image issues when she was diagnosed with breast cancer. Early detection means her outlook is good after undergoing a lumpectomy and radiotherapy, but the experience gave her a renewed thirst for life - she took just one week off work after surgery - and made her more determined to pursue unethical practitioners who prey on the sick. ''I realised just how incredibly vulnerable you are. I knew that intellectually, I just didn't know emotionally what it actually feels like. You feel like you've been punched in the guts … I just feel really sad when other people in that vulnerable position are getting ripped off.'' But while patient complaints can be distressing, she says they are often an opportunity to improve health services. ''Most people who come to us want to know what went wrong and why and they want to make sure that what happened to them doesn't happen to somebody else. If people come to us angry and unhappy with each other and go away with that resolved so they can get on with their lives, then we feel like we've been successful.'' BETH WILSON'S CV BORN November 2, 1949, Hastings, Victoria.

EDUCATION ■1961-65 Mornington High. ■1971-77 Monash University (bachelor of arts and law). CAREER ■1977-78 Librarian, Comalco.

■1979-80 Research assistant, Monash University. ■1981-82 Consultant, national survey of law libraries. ■1983-85 Manager, technical services, Telecom Headquarters library. ■1985-89 Librarian, Victorian Law Foundation. ■1985-90 Legal member, Social Security Appeals Tribunal.

■1989-90 Senior research officer, policy and legislation review, Health Department, Victoria. ■1990-92 Senior member, Workcare Appeals Board. ■1992-97 Chair, Psychosurgery Review Board. ■1992-97 President, Mental Health Review Board. ■1997-present Victorian Health Services Commissioner.

AWARDS ■2002 Monash University Distinguished Alumni medal. ■2003 Federal Centenary Medal for services to health. ■2004 RMIT honorary doctorate for health education. ■2008 Victorian Honour Roll of Women for services to women's health.