You're hunched over your keyboard, shovelling last night's leftovers into your mouth, struggling to meet the next deadline.

It's a familiar scene in many workplaces: taking a lunch break no longer means leaving your desk.

Or you're at home making dinner and your smart phone begins to vibrate. Your boss is apologetic, but she needs you to redraft the document you've been working on all week — by tomorrow morning.

For many of us, such scenarios represent the modern world of work, but that doesn't make them acceptable.

Economist Jim Stanford, the director of the Centre for Future Work at the Australia Institute, has calculated that as many as two-thirds of Australian workers are now regularly expected to put in some form of unpaid overtime.

And Dr Stanford said the situation is getting worse, not better.

"If you are a full-time worker, on average you are reporting about six hours a week of unpaid work for your employer," he said.

"That's a fair amount in a week, but add it up over a year and it's staggering — that's over 300 hours."

Calculated at the average Australian wage, that represents around $12,000 worth of labour per year per employee, Dr Stanford said.

"If most Australians thought who could they give a generous gift of $12,000 to, their employer wouldn't be at the top of the list," he said.

Part-time workers most vulnerable

Every year for the past eight years the Australia Institute has conducted a survey on work-life balance and unpaid overtime.

The 2016 report, due out in November, will show the issue crosses all professions and industries.

Australian Bureau of Statistics figures suggest that around 90 per cent of all new jobs created in Australia over the past 12 months were part-time or casual.

It is this group, according to Dr Stanford, who are most vulnerable.

"You have part-time workers who might only get 10 or 15 or 20 hours a week, and even they are being asked to stay longer and work for free," he said.

"Our survey showed that on average, even part-time workers are asked to do four hours of unpaid work a week.

"In their case, where their incomes are very low because they aren't getting enough hours, I think this unpaid work is especially exploitive."

Unspoken pressure to conform

It is possible to argue that employees are complicit in their own exploitation: that by regularly agreeing to work long hours for free, they feed expectations that unpaid overtime is acceptable.

But Dr Stanford says there are often unspoken pressures to conform.

"You don't have your boss over your shoulder saying: 'You must stay this extra two hours after work,'" he said.

"But the fact that it's so hard to get and keep a decent job means that workers are willing to push themselves more and more, in order to please their employer, keep their job and perhaps even get a promotion someday.

"Another obvious set of consequences is that if employers can get you to work longer for free, then they are not going to hire someone new to do that extra work.

"I believe that unpaid work is one of the factors behind the very slow rate of job creation that we are seeing in the labour market."

Experience or exploitation?

University of Adelaide law professor Andrew Stewart also see worrying signs in the growth of dodgy internships across the economies of the Western world.

Professor Stewart estimates around 75 per cent of all college graduates in the United States now undertake some form of internship with a company; with many such arrangements veering toward abuse.

"One way we can think about this is avoiding our minimum wage laws," he said.

"There are circumstances in which companies or organisations may get jobseekers to work for free, to get them to do productive work, but without paying them minimum wage."

In other circumstances, people are taken on as interns, but given no meaningful form of training or opportunity to practice their skills.

They essentially become the office "dogsbody". Such situations, Professor Stewart said, not only damage the intern, they also have a flow-on effect, because they steal jobs from low-paid workers who, as a consequence, are denied employment.

Internships for the highest bidder

Professor Stewart said there was also an opportunity issue at play.

"It's pretty obvious that people who come from wealthier or more privileged backgrounds are much more likely to be able to afford to work for free for lengthy periods of time to break into a particular industry or a particular job than people from lower socio-economic backgrounds," he said.

"There's a real issue here about access to professions and social mobility.

"Another example we found is internships being auctioned off; that is, the internship goes to the highest bidder.

"Not only are those organisations saying that you can come and do your job if you pay us money to give you the privilege of working for us, but we are going to take the wealthiest person, the person who can most put up the largest sum of money."

Trend has long-term implications

While the "pernicious" practice of charging people for internships remains rare in Australia, it has become increasingly common in the United States, according to Professor Stewart.

Dr Stanford is not confident that growing wage inequality and the rising tide of worker exploitation will be checked anytime soon.

Continuing uncertainty in the jobs market, he says, will likely quell resentment in the short-term, but he does believe there will eventually be a backlash if the situation is left to continue.

And there is a financial imperative: the loss of income for a worker translates into a loss of spending power in the economy as a whole.

"If you add that up across the labour force you're looking at roughly about $120 billion a year or something like 7 per cent of GDP that isn't being paid," he said.

"That drains spending power, it drains economic growth."

The need to rein-in dodgy internships and other exploitative work practices isn't just a moral issue, Dr Stanford argues, it's also has long-term economic implications, which shouldn't be underestimated.

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