They may say that their car has broken down and they need to phone someone for help. They may pretend to be a workman, saying that they need to check your electricity or water. They might even claim to be from the council and that they are carrying out a local survey. Whatever reason a caller gives, you need to be sure that they aren't just trying to get into your home to steal something.

There are around 12,000 incidents of "distraction burglary" each year, where callers get into homes and then steal cash or valuables while the occupier is distracted in some way. Sometimes they work in pairs, with one doing the talking while the other is stealing and they often target the elderly.

Be on your guard every time the doorbell rings, or there's a knock at your door. Look out of your window to see who's there first and if you don't know who the person is, open the window slightly and talk to them that way, rather than opening your door. Alternatively, have a viewer fitted in your front door so that you can take a good look at who's there first. If your eyesight isn't so good, don't worry as you can now get wide-angle viewers to help you see better.

Put the door chain or door bar on before opening the door and talk through the gap. You could even fit a small mirror to the wall next to the door so that you can easily see the person you are talking to. When the caller has left and you've closed the door, don't forget to unhook the chain so that any friend or relative you have given a key to can still get in.

Make sure your back door is locked if someone knocks at your front door. Sometimes thieves work together with one coming in the back way, while the other keeps you talking at the front.

Keeping the chain on the door, ask callers from the council or any other organization to pass through some identification. If you need your glasses to check this don't think it's rude to close the door and go and get them. A genuine caller won't mind. If you're still not sure, ask the caller to leave and tell them to write and make an appointment so that someone else can be with you the next time they call. The basic rule is if you don't know the person at your door don't let them in.

As part of the Government's "Stop, Chain, Check" campaign, local councils, social services and Age Concern centers have further information they can provide to older people. They can also help with door viewers, chains and mirrors, and in certain circumstances, may be able to supply a personal attack alarm that connects through to a control center.