Almost every day, a new opinion poll or survey hits the headlines. Many of these are carried out over the phone or via email, but a large number are conducted face to face by a market researcher in the street or in people's homes. Someone has to do these interviews and if you are friendly, open and happy to keep introducing yourself to strangers, that could be you – making some useful extra cash in the eve- nings and at weekends.

Market researcher is certainly not a job for the introverted. It involves knocking on people's doors and asking them to tell you, for example, which newspapers and magazines they read, what financial products they have or what they think of the Government. Being able to cope with rejection and having doors slammed in your face also helps – though, with good communication skills, this shouldn't happen too often.

Companies such as Ipsos Mori ( www.ipsos-mori.com) use interviewers constantly. They come from all walks of life and are given training before being let out into the world to ask questions. "Every applicant is asked to complete an application form, followed by a screening conversation with one of our experienced trainers," says Jane A'Court from Ipsos Mori.

"Successful applicants are invited to an assessment and training session, which lasts three days and is a combination of classroom and practical sessions. If they pass this, they join our panel, and on the first day of 'live' working they are accompanied by an experienced supervisor."

Much of the work is done in the evenings and at weekends as it tends to involve speaking to people in their own homes. According to Ms A'Court, a typical weekend shift would start at 1pm and finish around 8pm.

Sometimes researchers are simply given a few roads to try with a quota of interviews to conduct. They just have to keep knocking on doors until they fulfil their quota. At other times, they are given preselected addresses to contact and, often, specific people in those homes, such as the youngest member of the household or females only.

The researchers are paid per completed interview but their wages are topped up as they learn the ropes. They can expect to receive between £8 and £10 for each basic interview carried out. Generally, pay rates are a bit higher in London and the South-east than in the rest of the UK. The preselected interviews can be more demanding to conduct so researchers are paid more for these.

There are also bonuses if you meet your quotas.

'It's more fun than office work and there's a lot more variety'

Ann Smith, 28, from Hullbridge in Essex, has been a researcher for six years. She was working full-time for Ipsos Mori but has now moved part-time.

"It's more fun than office work and there's a lot more variety in it," she says. "I have a six-month-old son now and I can fit in the work when my husband is home in the evenings and at weekends."

Ann is paid the rate for the South-east, which averages out at around £9.50 an hour. "You could live off it," she adds. "I did it full-time for a year and made a living out of it."

"I really enjoy working with the public. No day is ever the same. You do have to cope with rejection but it doesn't bother me any more. My door-stepping techniques have improved over time."