Listening to constant dog barking is not only an annoyance to you, but also your neigbours. Dog barking is often at its most excessive when you leave your dog alone in the house (read our article Dog Barking When Left Alone).
With patience and training it is possible to reduce or even eliminate excessive dog barking. Sometimes this needs the help of a good dog behaviourist, but you can find some useful tips in our article How to Stop Dog Barking.