The first defense of any compound will be its location. The more isolated your compound is the less likely it is to face a major attack. Pay attention to natural formations such as cliffs thick undergrowth or turbulent waterways that can be used as natural barriers.

Also consider the climate your compound is located in. Depending on your location your defenses may need to protect your compound from the elements more often then zombies. Each environment offers its own survival challenges, and it is best to consider these before you start to plan your defense.

• Islands
• Deserts
• Arctic Tundra

Ditches

Against zombie attack ditches would likely be nearly useless. In fact depending on the depth of the ditch and the slope of the side facing the compound they may even be a liability. If the ditch is deep enough to block line of sight defenders would not be able to target any zombies that fall in. On the other hand, against raiders a ditch could be very useful in slowing or disabling vehicles and for providing cover for defenders.

Barbed wire

In conventional warfare barbed wire acts as deterrent by displaying an ability to inflict pain. While zombie are immune to fear and do not feel pain barbed wire still is a powerful defense. This is because the sharp wire barbs can easily catch on clothing hair or rotting flesh. This will likely slow down any zombie that approaches your compound long enough for it to be dispatched. In the first World War solders quickly discovered that metal containers such as tin cans can be attach to the wires ensuring that any intruder will make a hell of a racket.

Chain linked fencing

The main advantage of chain link fencing is that it take very little time to build which can be useful when first setting up a compound. Also its transparency allows you a clear view of everything outside the compound. Of course this means that anyone outside the compound can also see you. Chain link fencing is very effective against zombie attack but it will provide little protection from raiders with firearms. In general chain link fences should be used as a temporary defense while more substantial defenses are being built, in isolated compounds where raider attack is unlikely, or for protecting large areas from zombie infestation.

Masonry

There are many problems with the use of masonry for defense. First a stone or brick wall will take a long time to build, especially in colder areas because the construction cannot take place if it is below freezing.
Masonry does offer one great advantage over other defenses however. A properly designed wall can provide protection from raiders with firearms. For strengthening the defenses of a already established compound masonry walls are a excellent choice.

You will need to organize a rotating watch duty.
Lookout towers can be placed at regular intervals to extend the field of view of each guard meaning less guards will be needed. Lookouts should be armed with an accurate firearm such as a bolt action rifle to deal with any undead that wander into the area.

All these precautions will hopefully keep the zombie hordes at bay. But that does not mean that your compound is safe. Infectious agents can still make their way into your compound. The most likely ways for this to happen are infected people or their remains entering the compound and spreading the infection, and gear being brought into the compound with infected body fluids. The easiest way to prevent this is to require all members to follow these basic rules.

• Anyone entering/reentering the compound must agree to a full body search for any wounds before being allowed to enter.

• It is forbidden for a person to attempt to protect a zombie from harm

• It is forbidden for a person to assist an infected person in an attempt to bypass the compound's security.

• All equipment that has come into contact with infected body fluids must be sterilized before it can be handled within the compound.

• All bodies must be disposed of by burning at the first opportunity.