One of the main reasons for this behavior problem is because of how we greet our dogs.
The dog is usually excited that company is there and when we greet we are bending over the dog.
If you think about it from the dog's point of view the dog is looking up at the person, the guest is towering over the dog.
This body posture can intimidate a submissive dog which triggers the urination.
It's important for you or your guests to keep the greeting very low-key.
When your dog gets excited your dog has a much more difficult time controlling his bodily functions.
Pay close attention to your body language.
Don't lean over your dog.
Squat down so you are not bending over your dog, this way you can greet your dog without triggering the submissive urination.
Have treats close to the front door when you come in.
This way you can grab some or your guests can.
When you greet your dog you can toss the treats a few feet in front of your dog.
This will get your dog to focus on the treats and not so much on your greeting.
You don't want to give your dog the treat from your hand because you will be bending over your dog.
Once your dog calms a little have your guests come in and sit down.
This way your dog will be able to come over and greet your guests without them standing over your dog.
Most dogs calm down a few minutes after you come home or your guests arrive.
You want to try and get your dog to calm as quickly as possible.
Dogs that have this problem are usually a little fearful.
Don't yell or scream when this behavior occurs.
It will only make it worse.
Try to build your dogs confidence a little.
This can be done through positive training and agility training.
Training your dog in agility can do a lot to develop confidence.