Housebreaking an Adult Dog

It might seem like housebreaking adult dogs is more difficult than housetraining a puppy, however, adult dogs have a longer attention span and can focus better. Even older dogs that have been adopted from an animal shelter or humane society may never have been taught to go outdoors - but they can be. Housebreaking adult dogs is not a complicated process, but it does require consistency, patience, and plenty of praise.

Before you begin:

If your dog was reliably housetained previously and has now begun to have accidents, it's best to take him to the vet to check for any underlying medical conditions that may be causing him to eliminate inappropriately. Physical issues like kidney disease, Cushings Disease and liver disease can cause dogs to drink more and thus eliminate more. Canine cognitive dysfunction (dementia) may also cause dogs to forget their housetraining.
Accidents will happen. Don't lose your temper or punish your dog. Clean the area very well, as dogs are always tempted to go where they can smell other urine or feces.

Let the Housetraining Begin...

Designate an area that you want your dog to eliminate. This is where you will always take her. Eventually, the goal is to give her a vocal command and have her go their on her own to do her "business".
Choose a verbal command. "Go pee!" or "Go poop!" is simple, but if you find that embarassing, choose something else (remember, you can use any words or combination of words you want -- even ones that don't make sense! -- so long as you use them consistently).
Take your dog out on a schedule, several times a day. For instance, you might decide to take her out first thing in the morning, after breakfast, in the afternoon, after dinner, and before bedtime. Keep a consistent feeding schedule since it will make it easier to housetrain her.
Immediately bring your dog to the elimination area. Don't allow her to sniff this or that, or get side-tracked in any way. Take her straight to the spot, give her the verbal command, and wait. After she goes, praise her immediately - you want her to associate going outdoors with happy things. Let her know that you're pleased that she's eliminated outdoors.
Supervise your pooch. Don't give her a chance to eliminate indoors if at all possible. You can confine her to the same room that you're in, and watch her for signs that she needs to go (ie. sniffing or circling).
If you have to leave her alone for a while, consider a crate or kennel. Don't make it too big, as you don't want your dog to divide the kennel into a "bedroom" and a "bathroom" area! It should be just large enough for her to stand, lie down, and turn around comfortably. When you return home, immediately take her outdoors to her elimination area, say the word, and praise her when she's done.
If you catch her in the act of eliminating inside, do something to interrupt her. Then take her outside to the same spot, give the verbal command, and praise her if she finishes going there.

With time and consistency, housebreaking adult dogs (just as with puppies) can be done successfully.