The union is not just concerned about "workplace, working conditions and wages, but also about housing affordability, marriage equality and refugee rights".

"A lot of the growing membership of younger members are wanting to campaign on progressive issues," she said. "We've really branched out in the work that we do. Bargaining is a very small part of our work and I guess it's what most people traditionally expect to see the union doing."

As the secretary of the Australian Services Union NSW & ACT branch since 2015, Ms Lang said she has seen her membership grow 5.5 per cent in the past year - a net increase from 11,681 to 12,298 members. The union represents a broad range of industries to cover Sydney Water, airline check-in staff, IT workers, community and disability services.

It has created an army of 300 organisers in workplaces in two years. But that growth is anything but typical.

Across the country, union membership has plummeted to an all-time low of 13.3 per cent with 800,800 female members and 746,400 male members. Nurses unions are well organised and among female-dominated unions experiencing spikes in membership as employment opportunities in the health industry grow.

NSW and South Australia are the only states that increased membership between August 2014 and August 2016. The numbers grew from 498,100 and 525,400 in NSW, an increase from 15.3 per cent to 15.5 per cent. In South Australia, the increase was from 112,600 to 113,600, taking the percentage from 15.7 to 15.8. Ms Lang said her members in community and disability services were growing most rapidly. The union has campaigned on funding for the National Disability Insurance Scheme, minimum standards of service delivery and job security.

"Bargaining against employers in the community sector doesn't really make a lot of sense because they don't control the purse strings, government does," she said. "It's actually been about campaigning to change how governments fund the sector, how they value and regulate the sector to drive professionalism and standards."

Recovering numbers

In NSW, even unions gutted by corruption scandals have managed to recover numbers.

Health Services Union NSW secretary Gerard Hayes was tasked with cleaning up the union after Kathy Jackson and Michael Williamson tarnished its reputation through alleged corruption. The union lost 6000 members in just six months in 2011.

The privatisation of hospital services and loss of death and disability protections are among issues that have galvanised members.

In NSW, the union had 28,992 members in 2012. It now has 35,000.

"We had a debt of $23 million with a $200,000 overdraft in 2012. We will be fully out of debt next year," Mr Hayes said.

AMWU NSW secretary, Steve Murphy, 41, said the closure of major manufacturing companies, including Electrolux in Orange, had led to a steady 3 to 4 per cent decline in members.

"With our new members in and old members out, we have had about 1.2 per cent growth this year," he said.

The union is reaching out to new members on Facebook and text messages and on smaller work sites. But in Victoria, the union has struggled with massive job losses from the closure of car manufacturing plants.

Former ACTU assistant secretary Tim Lyons from "think tank" Per Capita said the number of manufacturing jobs has not only fallen as a proportion of all jobs for about 10 years, but has fallen in absolute terms.

"That has affected all of the unions with a manufacturing base, which is essentially all of the key private sector unions with the exception of the [Shop Distributive & Allied Employees Association]," he said. "You've [also] seen a great deal of outsourcing over a 20-year period and those jobs are more insecure and harder to organise."

Lyons said unions have failed to effectively organise in growth service industries outside health care and community services.

"It's not going to turn around unless there's an actual plan to organise people and that's what's missing. You can see those unions which have a plan to organise and grow are either holding their ground or moving," he said.

Unlike his predecessor, Tim Ayers who is now a Labor Senate candidate, Mr Murphy, who started work as a fitter in Newcastle, says he has no interest in a political career.

"I just don't think that's the main gain," he said. "We should have a relationship with the ALP, but it should be on our terms.

"I think working people do have an interest in politics, but their expectation is that their leaders put their members first."

Mel Gatfield, the NSW secretary of United Voice, jokes she is a "proud dual citizen" to make the point she has no interest in entering politics.

"Not my thing," she said. "When you give people the skills, the tools and the confidence to do public speaking, lobby a politician or bargain against an employer, there is nothing like it."

Most of Gatfield's members are women who work in childcare as educators, in home care as careworkers, cleaners, casino and hotel workers.

Union membership has declined in small manufacturing industries but grown in home care and casino industries.

"We recruit a bunch of people every year, but the turnover in our industries is so high that people are moving around in the economy so they don't stay with us," she said. "We've got a really vibrant growing closed Facebook group in home care administered by old-style delegates."

Forced to innovate

Unions NSW secretary Mark Morey said the union movement had been forced to innovate, using online organising, artificial intelligence and more face-to-face contact. It is also helping introduce industrial protections for workers on online platforms, including Air Tasker.

The pendulum may be swinging back in favour of unions with workers frustrated over stagnant wage growth while company profits and CEO bonuses rise.

"The benefits of productivity are not being shared and so people have a real sense of inequality," he said. "There is an opportunity for unions ... and we have to re-energise and innovate to be relevant today, particularly to young people."

Political life does not appeal to Mr Morey, a former youth worker, and he hopes to stay for another term. "I think politics today is more of the same and I don't think you have the opportunities to reach out to people to change people's lives in such a broad way as you do with the union movement," he said.

Unions needs to appeal to younger people. The average age of members is 45.

His Victorian counterpart, Luke Hilakari, agrees.

Hilakari became the youngest leader of Trades Hall in Victoria at the age of 34 three years ago and says the average age of his organisers is 24. "Hiring young people to speak to other young people is the best way for us to identify issues and campaign about them," he said. "Unions have to evolve. They have to learn how to use social media and embrace new technology. That takes time, but I think we are there."

In the past two years the Trades Hall has established the Young Workers Centre in Melbourne to help young hospitality and retail workers facing exploitation and underpayment. "We are spending a lot of time working with young people educating them about their rights and trying to enforce them," he said. "We are seeing people paid anything between $7 and $14 per hour."

Embracing people of colour, young people and women as new members is part of the strategy Hilakari hopes will turn unions around as organisations "where people want to be".

Trades Hall is establishing a migrant workers' centre and is the only trades and labour council in Australia to have a dedicated women's team, focused on gender and family violence issues.

A renewed focus on old concepts of grassroots organising, town hall meetings and one-on-one conversations are part of the broader strategy to recruit new members. Trade Hall's energetic campaigning in the lead up to the state election was credited with helping get Labor elected, but it has not reversed the tide of decline. Australian Bureau of Statistics figures show union membership in Victoria fell from 393,300 to 381,300 (15.3 per cent to 14.1 per cent) between 2014 and 2016.

While Victoria's nurses union is booming, the offshoring of manufacturing and closure of major car makers has contributed to the overall decline.

"Victoria is a manufacturing state," says Hilakari.

But he sees scope for improvement with 70 per cent of Australian workers covered by awards or enterprise bargaining agreements and only 15 per cent unionised.

And while the ALP needs good politicians to represent workers in parliament, Hilakari says this is not a pathway he is considering.

His own path

The running joke in Australian Workers Union national president Daniel Walton's family is how he was supposed to study law.

His father Michael Walton is a NSW Supreme Court judge and former president of the NSW Industrial Relations Commission. His mother Therese was a court reporter and now works for the Transport Workers Union. His uncle Chris Walton is chief executive of white-collar union, Professionals Australia.

"It's still a running joke in the family that I was mean to do law," Walton said. Despite avoiding his family's influence, he ended up working in industrial relations.

"I've always had it around me but it was never something I set out to do. I was not political and never involved in Young Labor," he said. His lawyer sister who represents employers, turned out to be the "black sheep" of the family.

The 34-year-old has led the national and NSW branch of the AWU since last year and is credited with helping save thousands of jobs after the sale of Arrium's Whyalla steelworks. He also negotiated concessions at Port Kembla's Bluescope steelworks which helped keep steel making in Australia.

Deliberately avoiding family expectations to study law, Walton "skipped university" and worked as a chef before travelling overseas after leaving school and then taking a job as a handyman for the NSW Labor Council in 2003 during its Your Rights at Work Campaign. He was later offered a job working with former AWU leader Paul Howes.

The leader of Bill Shorten's old union has been advised to never say "never". But he said politics is "most definitely something that doesn't interest me at this point in time".

The Australian Federal Police raided Walton's offices in Sydney and Melbourne last month as part of an investigation into donations the union made a decade ago to activist group GetUp! when Mr Shorten was the union's leader.

During an interview with Fairfax Media before the raids, Mr Walton said holding the Labor leader's old job had "come with its own challenges". "Having the Opposition Leader formerly holding my role does seem to draw additional media and political attention," he said.

The AWU's memberships have been declining for a number of years, but some branches, including NSW, are starting to break even and show signs of growth.

"We have a long way to go," he said. "There is some significant structural change that we need to make across the organisation to get us fit for purpose with the modern workforce."

That includes organising members in small businesses. The AWU is testing a new model of organising hairdressers as ambassadors to form a new union. "People expect genuine industrial representation, not reflection on the glory days."