One of my dogs was always a big barker. I was able to stem the behavior (kind of) until the new neighbor moved in with a dog who was allowed to bark in the yard a LOT. My poor dog was going crazy because he knew he wasn't supposed to bark a lot outside. It was like he couldn't help himself when the neighbor dog barked, he was compelled to answer.
Things were getting pretty tense until Sam Kabbel came to my house and listened to all the details of the problem and my dog's personality. She suggested a very simple solution to try. I felt kind of dumb for not figuring it out myself, but that's why she is a professional pet behavior counselor and I'm not (I'm a veterinarian)!
The solution was simple, easy, didn't scare my dog, and IT WORKED! Like almost instantly! I think Sam is a genius and recommend her service to people all the time. Call her if you have any pet problem, I bet she can help.