PERHAPS we should have some sympathy for those poor souls involved in direct-dial operations in call centres.

It cannot be an easy job ringing up total strangers all day with a view to selling them something.

Relentless chirpiness must be difficult to maintain in the face of reactions which probably range from outright hostility to bored indifference. These people who disturb our tea -- or make us return to the telephone as we are about to get in the car -- are fellow members of the human race who are simply trying to make a living in the face of great frustration.

Some of them crack under the strain, as demonstrated to a friend who took a call from one chap who was probably on his last day in the job. After a routine expression of disinterest, the caller became aggressive, indicated that he knew where my friend lived and threatened to put his windows in.

To my knowledge this is not in the careful script to which tele-sales personnel are expected to adhere. But it is understandable and I hope this individual has now settled in to an alternative career which suits his talents better.

These "cold calls" are such a part of modern life that everybody needs to develop their own technique for dealing with them. Buying things is one way, but I suspect that most people simply do not want to know -- whatever it is.

One sweet lady of my acquaintance has a devastating method for making callers go away. "I'm afraid this is rented property," she says, lying through her teeth. It never fails.

But those of a more imaginative nature might try feigning madness: "Hello Tracey/Darren, thanks for calling -- I'm not really allowed to use the telephone 'cos it might blow up," or: "The warden here is a very nice man and he has millions and trillions of pounds in a big bag round his neck," or: "He could buy one of those conservatories and we would have somewhere for all the furry creatures."

An added effect might be to ask your partner to shout sternly in the background: "Put that 'phone down. It's time for your enema."

But what am I saying? Such conduct is not really to be encouraged, even though another friend once derived some weird satisfaction from engaging Jehovah's Witnesses in such detailed conversation that they spent most of the lengthy session trying to edge away from him and escape into the street.

If I get calls, I try to remain civil even though I have absolutely no intention of responding when I am told I filled in a survey recently. Oh no, I didn't.

Most callers go away reasonably quickly, but we have had problems with British Gas. Some while ago we considered asking them to become our household power supplier, but after filling in a form we changed our minds during the "cooling off" period and did not transfer away from our existing company. They do not seem to have got the message yet.

We continue to get sales calls and I point out every time that each of the previous half dozen callers has promised to delete us from the list they use. One day they will stop ringing us -- maybe.