Deborah Mattinson, Gordon Brown's chief political pollster and author of Talking To A Brick Wall talks to Total Politics magazine about why focus groups are still important references for politicians.

Eight swing voters assemble in a suburban sitting room. Clutching a glass of Coca-Cola or wine, scrambling for the comfy chair rather than share the sofa with a stranger, they may be shy at first, but gradually gain confidence as the evening wears on. It's a focus group and their views count.

Psychologists developed focus groups in the 1950s to complement statistical data. They are small scale, informal and discursive, providing deeper, diagnostic insight into consumer behaviour. Margaret Thatcher's adviser, Tim Bell, pioneered their application to UK politics in 1978 while developing Saatchi's highly effective "Labour isn't working" campaign.

To read more click here, to buy Deborah's Talking To A Brick Wall for £17.99 click here.