If you don't have any fencing around your property then you may want to have a chain link fence installed. However, if you have a large property then you may not be in the position of fencing it all in right now, or you may not even feel that you need to go to this extreme. If you are trying to decide how much of your yard you should fence in then you can consider the following:
Do you want the fence for security purposes?
If you want the fence to keep people from walking right onto your property and coming up to your home then you may want to consider fencing in an area all the way around the house. You don't necessarily need to fence in the entire border of your property, but you can use the fence to dictate a front yard and a back yard area that lets people know they aren't invited to trespass in those sections of the property. You can go with an even more cost effective form of fencing around the entire property that may not keep people out, but which will let people know that you own that land as well.
Are you just looking for a way to prevent your dog from running off?
If you really just need an area to let your dog go to the bathroom knowing they can't run away then you can figure out a good spot for a dog run and fence in a good size area that will become their own run where they can relieve themselves and let off some steam in the yard and sunshine.
Are you looking for a way to protect your garden?
If you have a garden and you don't want stray dogs, deer and other animals getting into it then you really only need to fence the garden area in. When you are having the garden fenced, make sure you consider whether or not you may want to expand the garden area in the future. If there is any chance of you wanting to do so then have the fence go out further so you will have all the room you may need for the garden in the future.
Once you decide exactly where you want a chain link fence installed you should go ahead and act on it. You'll then be able to rest assured that the goal you have in mind will be achieved so you can move on to the next project you want to take care of around your yard or home.
For more information, talk to a professional like Invisible Fence Brand by Coyner Associates.