Dealing with shoppers nowadays isn't just about a polite exchange of words alongside the exchange of cash. The paying public can be difficult, rude - even violent. Rather than leave dealing with the tricky customers to security or private detectives, the managers of Cribbs Causeway, the out-of-town shopping complex near Bristol which opened this week, have decided to hold specific courses for all the 60 or more staff, from cleaners to top managers.
The training consultant, Jonathan Coles, begins to elaborate a modus operandi of appropriate response. "These are cues or clues that the situation is getting more serious for you. You are beginning to think about personal safety, and you need to apply some calming techniques."
The 10 trainees listen intently, and chip in with suggestions about what to do when faced with someone who is losing control. They could be simply frustrated or they could have forgotten to take essential medication. If someone is shouting, talk quietly, says Coles. If they're gesturing wildly, hold out your hands, palms out, in a gesture of submission.
You could try responding assertively, he says, but do it just once, and go back to calming if it doesn't work. Above all, never turn your back, and try to signal to a colleague or to the watching security cameras if you are in difficulty.
"The focus for staff in shopping centres is usually directed more to the criminal than the customer, and in dealing with violence," says the centre's manager, Jonathan Duckworth, who is also one of the trainees at the session.
"But you have to make the staff understand what people might want, rather than simply saying that they can't come in. We are a shopping centre not a battleground and we expect people to behave as if they are in a shopping centre. The behaviour of the public is going to be very, very good."
Assessments of other malls' performance suggests that around 300,000 people a week will visit the 130 shops. Cribbs Causeway has been designed as a very attractive environment for shoppers, light, clean and crisp, with a glazed atrium over the entire length. With 7,000 parking spaces, a leisure complex with a 12-screen multiplex cinema, and its location on the northern edge of Bristol, near to the M5 and M4 motorway network, Cribbs Causeway's catchment area stretches from Worcester to Taunton on the M5 and from Swindon to Swansea on the M4.
But while the new mall might be built for shopping till you're dropping, it's inevitably going to assume a whole range of meanings for the people who go there. And what about the mall-rats, those teenagers who make the mall their home from home, turning a retail environment into a theatre, complete with elaborately coded grooming and courtship rituals?
"They're our customers or potential customers, too", Duckworth says. "We have to treat people as individuals and not apply stereotypes. If there are types of behaviour that you don't like, you have to deal with them in other ways than simply going "Oi! Stop!" It has to be professional, just like shopping should be."
Back at the training session, it is revealed that the staff's ultimate weapon in dealing with awkward customers will be offering them a nice cup of tea. The touchy-feely management style has a very Californian feel to it, as befits the first mega-mall on England's laid-back west coast. But never, ever, turn your back - right?