What are your chances of working in retirement?

We're all going to be expected to work longer in future. From December 2018, the state pension age is set to start climbing, reaching 67 between 2026 and 2028. Those people who are young adults now are expected to have to work well into their seventies.

Meanwhile, more than 900,000 current workers are expected to retire without any private pension, with many desperate to add to their state pension by working longer.

A government report produced last year found that people remain, on average, just as productive up to the age of seventy. And, since the compulsory retirement age of 65 was scrapped in 2011, more than a million over-sixty-fives in the UK have chosen to stay in work - half of people reaching state pension age this year plan to do so, Prudential researchers found last year.

"Working up to and beyond state pension age, for those who can and want to do this, offers a real alternative to saving more or having a lower than ideal income in retirement," says Chris Curry, director of the Pensions Policy Institute.

But staying on isn't always an option. Ageism is still rife in the workplace, with, for example, a survey last year from the Institute of Leadership and Management (ILM) finding that six out of ten managers believe that the over-50s have low or very low potential to progress.

It can also be tough for those in manual occupations or in poor health to carry on working full-time until their late sixties or seventies.

One answer is to shift to a part-time or flexible job.

"Employers need to adopt age friendly policies such as flexible working, phased retirement, family care leave and even gap breaks," says minister of state for pensions Ros Altmann.

"This can facilitate a new type of retirement, where people cut down rather than suddenly stop working, where health and wellbeing policies take account of older workers' needs (including support for women through the menopause) and where employers enable staff to combine work with caring responsibilities."

The government is also keen to push the idea of self-employment for older people, saying it gives them financial independence, flexibility in working hours and the opportunity to rise to a new professional challenge.

Older entrepreneurs are more likely to succeed, according to last year's report, and there has been a 140% increase in over-65s running their own business since 2000.

It's an attractive picture. However, for many, being self-employed or taking up flexible working isn't all that it sounds. Both terms are often used to mask irregular, casual work that can pay less than the minimum wage. And part-time jobs also tend to be at the bottom of the scale in terms of seniority - few senior managers get to work mornings only.

Worryingly, there are some that see this as acceptable. Earlier this month, it emerged that senior Conservative minister Owen Paterson suggested to a cabinet meeting three years ago that pensioners should be put to work picking fruit in the fields in order to fend off competition from eastern European immigrants.

And, he suggested, because 'they may be a bit slower doing the work', these pensioners should be paid less than the minimum wage.

Certainly, there are plenty of employers out there who are already conning young and elderly alike into jobs that pay little or nothing at all.

Earlier this year, the TUC estimated that a quarter of a million British workers are being paid less than the legal minimum wage. In some cases, this is because they are doing piecework on a self-employed basis; in others, they're not paid for travelling time.

And, given the levels of ageism in the workplace, many of these jobs are all that older people can get.

"Younger and older workers are both more vulnerable to disadvantage, because of their concentration in part-time, low-paid, temporary and insecure posts where conditions of employment and access to training are generally poorer," say researchers from the Joseph Rowntree Foundation.

"They are also more likely to change jobs frequently and to have periods of unemployment, but have less financial support, since redundancy pay is only available to those who have been with an employer for more than two years."

Part-time jobs are advertised in all the usual places. However, jobs website Indeed has a section for ads that specifically mention the possibility of taking on someone semi-retired. While many are low-paid jobs such as carer or delivery driver, there are usually plenty of more challenging or better-paid vacancies.

Meanwhile, Retired4Hire specialises in jobs for older people; as well as hosting ads, it allows people to post their CV and skills profile online. The site has rather more graduate-level jobs than Indeed.

And Retirement Reinvented has a page of vacancies for non-executive directorships, most of which are perfect for somebody at the end of a high-flying career.

However, the best way to find a job in retirement is often to simply ask around - this way, your skills and experience are much more likely to be appreciated.