Great advice so far!
We have a unique situation because, first, we have 5 adult dogs, second, we often have puppies, third, we do not have kennels. Here is what we do:
Our "dog house" is in the garage. We have a large, double garage, attached to the hallway of our home. We put a doggie door in the hallway door so that they can go in or out of the house at will. When we are gone, however, sometimes we lock the doggie door, sometimes we just block the hallway. (If the weather is cold, I leave the doggie door unlocked and block the hallway off so they can only be in the hall, not in any room. They can still go to the garage if they want.
We also have a doggie door to the completely fenced back yard, but since our dogs bark, we don't let them run the full yard when we are gone. We block off the yard so that they only have about a 15'X15' area. The fence is solid wood so they can't see beyond it (which helps because if they don't see things, often they won't bark.)
Since they are all together and since these areas are used by them even when we are home, they are comfortable there.
BUT if we will be gone for more than 4-5 hours, I lock the doggie door to the outside and I have a dog sitter come in and check on them about every 3 hours...to make sure all is well, to let them out to potty, to play ball with them and to make sure they have water.
When we have puppies we usually stay home with them or have the dog sitter come and stay with them. (Oh, and the puppies are kept in a large area by using an x-pen, we keep them in the spare bedroom until they are about 3 weeks old, then move them to the dining room.)
It works for us!