Installing a burglar alarm needn't be expensive and it can go along way to deterring a would be burlgar. Government statistics show that around 60% of burglaries carried out on homes with burglar alarms are unsuccessful. This therefore suggests that installing a burglar alarm is a major deterrent to potential burglars. Have a look at the houses on your street - if most have an alarm system installed and yours does not then it is more likely that a burglar may target your house.

Burglar alarms are widely available and range from kits that you can install yourself from your local DIY shop to more expensive sophisticated systems that need to be professionally installed.

Ask the crime prevention officer at your local police station for advice before you buy an alarm. The British Security Industry Association recommends that householders use a professional alarm installation company registered with a police recognised "alarm inspectorate" - so ask to see your security company's registration documents, and look for the following accreditation:

- NSI (National Security Inspectorate)

- NACOSS (National Approval Council for Security Systems)

- ICON (an approval scheme run by NSI)

- SSAIB (Security Systems and Alarms Inspection Board)

The most trust-worthy companies will offer you a free survey quotation without obligation. Try to avoid companies who use scare tactics and who seem more interested in the actual sale rather than the security of your property. If you think that any company is unethical in the way they approach you then you should perhaps consider reporting them to your local police and/or trading standards office.

The most common form of alarm is a traditional "bells" only alarm which costs around 500 pounds to install plus an optional yearly maintenance contract of around 65 pounds.

The more expensive option is a "monitored alarm", which may be worth thinking about if you have a lot of valuable property, or you live somewhere isolated. Monitored alarms are connected to an "alarm receiving centre" where someone will alert the police if an intruder is detected. They cost between 800 pounds and 900 pounds to install and around 200 pounds each year for monitoring and maintenance.

The big difference between a bells-only and a monitored burglar alarm is police response. You need to know that the police will not respond to a bells only alarm unless they receive confirmation from you, your family, or someone else nearby, that there is a burglary in progress.

Since October 2001 newly installed monitored alarms must also use "confirmation" technology to receive a police response. Here, people at the alarm-receiving centre check using either CCTV (to see an intruder), an audio connection (to hear an intruder) or something called "sequential confirmation". Sequential confirmation means detecting an intruder using sensors in a number of different places in or around you home - to spot if someone is moving around.

If all of this sounds too expensive so far then you can opt to install your own alarm. Although a self installed alarm system may not be as reliable as a professionally installed system, it can still act as a deterrent as well as cost less money. Remember, a badly-fitted alarm can create problems in itself. Don't install a DIY system unless you have the electrical knowledge and practical skill to do so.

Before deciding on the type of alarm to install check with your insurance company first. They may offer discounts off your premium depending on the type you have fitted and the kind of installer you use. This could help make your choice a little easier. If installing your own alarm, make sure it meets BS6707 requirements. And if you get a professional in to install it, ensure they meet BS4737 standards, or the new European Standard EN50131-1.