When you find your pup having accidents, identify the cause, make a change, and then go back to the basics.

By Dr. Gayle Watkins, PhD
1. You aren't responding quickly enough to signs that your pup needs to potty. Early in your pup's life, you have only seconds to respond to indications that it needs to go outside to potty. It is your job to watch your pup for these signs! When your pup hits four months or so, you may have minutes to respond.
Some of the most common signs that pups need to go out are:
• circling
• suddenly breaking off from play
• sniffing
• acting anxious or restless
• rattling around in the crate
• pawing the door of the crate or expen
• disappearing into another room
• whining
• going to the door
2. You are giving your pup too much space. Unless your puppy is a giant breed, until about 3 months of age it does not need more than about eight square feet of space, which is four panels of your exercise pen. More than that and your pup is likely to potty in the pen or crate.
3. You are leaving it alone for too long. How long is too long? After 8 weeks of age, medium- and large-breed pups can usually hold their urine the same number of hours as their age in months plus one, but only when confined in a quiet, boring environment. Toy and small breed pups may only make it half that long. So if your golden retriever pup is 3 months old, it can likely be left alone while you are out for no more than 4 hours. Limit your trips to two hours for your toy poodle pup.
If you need to leave your pup alone for more than this, you should put a potty box or pan into the expen so your pup has an acceptable place to potty. To fit it in, expand your ex-pen just enough to accommodate the pan. Then when you get home, remove the pan and reduce the size of the ex-pen to the smaller, four-panel size.
4. You are giving your pup too much freedom. Up until five or six months of age, your pup should never be loose in the house unsupervised. Supervising means being engaged with your pup and directly monitoring at all times. It will be those few seconds that you are not paying attention that your pup will slip away and have an accident. Being successful at this early age is the KEY to having a fully potty-trained dog for the rest of your lives together so if you are checking your email or making dinner, put your pup in the crate or expen, or tether it to you.
Tether your puppy to you by attaching its leash or tagline to its collar and tying the end to your belt loop, stuffing it in your pocket, or looping the leash handle around your wrist. This way you'll know if your pup tries to move away to potty or pulls to go outside.
5. You think your pup is more house-trained than it is. Most pups' housetraining doesn't follow a straight path. Instead, they'll be great one day and not so good the next. Just because your pup has a good few days or a week, don't assume that it is fully housetrained. Instead, be disciplined--keep your pup confined, limit its freedom, and follow the steps in taking your pup outside.
6. Something has changed in your pup's life. What kinds of changes can cause pups to struggle with housetraining? All of the things we discuss in the Traveling and Challenges modules, like illness, weather, and activities such as swimming.

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