Professor Bob Cialdini has met ministers in Downing Street as part of Tony Blair and Gordon Brown's wide-ranging reappraisal and discussed with them his 'science of compliance' - which persuades people to change long-held patterns of behaviour for good.
That area of Cialdini's work is said to have excited ministers. He also learnt from car salesmen a technique called 'low-balling' - getting a customer to commit to buy a car at a bargain price, and then adding last-minute charges without losing the deal.
Once people have decided on a course of action, concludes Cialdini of Arizona State University, they will go to extraordinary lengths to adhere to it. For instance, his solution to cutting down on the seven million NHS appointments missed each year is, associates say, likely to involve getting people to 'commit' to turning up by having the patient, not staff, fill in a card recording a future consultation.
The present approach of many clinics that put up posters saying, for instance, that '257 people this year have missed appointments' has the unintended consequence of validating precisely that kind of behaviour in patients' minds.
Take down or redesign the poster, the Cialdini principle suggests, and you will bring down wasted NHS time.
He described the ministers' reaction to his message as 'a beautiful response'. 'There is recognition of the importance of behaviour change in encouraging public service progress. We must motivate our citizens in ways that are socially beneficial,' he told The Observer
While embracing his work, Downing Street recognises that its critics may seize on its new-found fascination with Cialdini as a case of 'New Labour meets New Age'.
Cialdini's website has the irrepressibly optimistic feel of a self-improvement course. Trumpeting his achievements 'in the field of influence and persuasion - Dr Cialdini is the most cited social psychologist in the world today' - it includes a string of gushing testimonials to the work- and life-changing effects of his presentations and writings.
He holds dual professorships in psychology and marketing, and comes over in person as part researcher and part master salesman.
Cialdini is the million-selling author of a book called Influence: The Psychology of Persuasion and is a hugely successful international speaker, trainer and consultant. His company, Influence At Work, has a string of blue-chip American corporate clients, and a burgeoning new UK subsidiary.
Next month, the UK arm's Steve Martin is due back in Downing Street for a more detailed discussion. Martin is convinced the professor's techniques could help cut the number of missed NHS appointments: 'We have evidence and studies that suggest this could be reduced significantly by making one or two small changes in the appointment system that would be cost-free.'
Under the influence
Bob Cialdini's six principles...and what they really mean:
Commitment/consistency Once people have set their minds on a course of action, it takes an awful lot to get them to admit they were wrong. This is great news not only if you're a used-car salesman but also if you are peddling a new political policy.
Authority If someone with authority or expertise tells you do something, you are much more likely to do it. It's why a milk company might, and indeed did, seek out someone like Lord Winsto, to help to advertise its product.
Social validation If you see a lot of people like you doing something, you are very likely to follow suit. That's one reason why major changes in attitudes on issues such as recycling happen.
Scarcity The rarer the goods or service, the more we want it. Great for adverts of the 'while stocks last' variety.
Liking/friendship People are much more likely to say 'yes' to someone they know, or at least like. If you're a teenager, that means you're much more likely to be convinced by a girlfriend or boyfriend than a parent, policeman - or politician.
Reciprocation You scratch my back, I'll scratch yours. One reason, Cialdini suggests, why Hare Krishna collectors do so well at airports is that they give out flowers.