Leaving a dog alone overnight is something that should be done only in unforeseen emergencies, unless the owner works the graveyard shift and being alone at night is part of the animal's normal routine. Otherwise, arrangements need to be made for someone to stay with the dog.
If a dog is not used to being left alone at night, it may experience separation anxiety as a result. This can cause the dog to bark for long periods of time. Constant barking is bad enough if it happens during the daytime, but if it occurs at night, the owner runs the of risk incurring the wrath of neighbors.
If a situation occurs where the owner simply cannot be home at night with the dog, a trusted friend or relative should be called for assistance. If a pet must be left alone, it should be put in its usual sleeping place with the door closed.