Alarm systems can significantly enhance security if installed and used properly.

Phony "Warning: These Premises Protected by the XYZ Company" signs are usually not effective; a serious burglar needs only look in the telephone directory to see whether an alarm company exists. Most companies won't let non-customers display their emblem, and the burglars know that, too. There's no harm in using such signs, but don't "expect" them to provide any protection.

If you are hiring out to have your home alarm installed, always use a licensed vendor to install, repair, or service an alarm system. While licenses do not guarantee honesty, it does indicate that the vendor has registered with the state, and has met the specified minimum criteria for your locale. In most cases, a license is predicated upon proof of adequate insurance and/or bonding, so you have that protection as well.

Local alarm systems (those which sound only on the protected premises) are much less effective, especially when local ordinances limit the time for which the signal can sound to avoid nuisance disturbance of neighbors. If you invest in such an alarm, you are counting on conscientious neighbors to call the police to respond. Having the signals from your alarm system monitored by a licensed vendor better assures that you get the protection you pay for when you install an alarm system. Other systems will dial your number at work or your cell phone and inform you of an alarm at home.

Remember the best alarm systems rely on phone lines. Check where the lines attach to the house. If they attach at the ground floor level, they should be routed through metal conduit to prevent them from being cut.

The best alarm systems are those which combine perimeter and interior detection devices. Every door should be protected with some type of switch device. Covering every window (or even every "downstairs window" in multi-story houses) can get very expensive very quickly; your decision should be guided by local experience with criminal entry through windows; if that's a common occurrence in your area, window protection is probably advisable. If not, interior protection may be adequate. If window protection is needed, glass-break sensors are the preferred device.

Interior devices cover a volume of space, and are typically wall-mounted. The least-susceptible to false alarm are passive infra-red sensors (which are really thermostats that detect the presence of a human intruder by comparing the 98.6 degree body heat to the usual ambient temperature in occupied space which is typically between fifty-five and seventy-five degrees). Pets, air currents, rodents, and other similar sources will not set off passive infrared devices, and thus generate minimal false alarms. Don't forget to provide coverage for any attic access in exposed or semi-exposed locations (like the garage). Consider installing one or more panic buttons at fixed locations, or obtaining one or more such devices which can be worn on a chain or key chain if you have members of the family with health problems or limited mobility.

You'll need to decide whether you intend to use the system when you're home, or only when you're out. If you want protection when you're at home, the system will have to have "zones" so you can arm the perimeter while leaving occupants freedom to move about.

Every system has a control panel of some type. In most home security systems, the controls are concealed in a closet or utility room, and only the controls necessary to operate the system are in occupied space. In most systems, these controls take the form of a touch-pad resembling the one on your telephone. You "arm" or "disarm" the system by punching in a code. Most users find it convenient for all members of the family to use the same code, but many systems are capable of multiple codes. Some systems are also capable of using arm codes with one less digit that the disarm codes, allowing you to have a household worker turn the system on when they leave, but unable to turn the system off. You'll need to consider how you want to use the system before making a decision about type and installation.

Installing the keypad inside the protected space prevents any access by unauthorized persons, but necessitates that there be a delay in signaling an intrusion (at least from the entrance where the control is located) in order to allow sufficient time for a family member to disarm the system upon entering. You can eliminate this delay by installing the touch-pad outside the protected perimeter. While this does subject the pad to attack, you can minimize the risk by installing it inside the garage rather than at the front door. Many people come and go through their garages, and inside installation of the touch-pad minimizes any opportunity for someone to attempt to defeat the system through that device.

If you have high-value assets inside your home, there are supplemental devices available to extend alarm protection to these items. You can alarm a closet used as an inside "strong-room", a display case for collectibles, a safe or vault, or wall-hung artwork. Any competent alarm vendor can assist in devising a means to protect almost any asset.

Alarm systems don't eat, sleep, get bored, or take vacations. They are, however, electro-mechanical devices subject to failure, and must be tested regularly to ensure they work as designed. Set up a test schedule with your vendor or alarm company; at least once monthly is highly recommended. If your alarm is a wireless system make sure it is self monitoring and will signal you if a battery is low.