well, I see that he's a small dog and small dogs tend to bark A LOT. why not use the cintronella spray collar that is more humane like Angie suggested? I know my mom's dog, Ginger does bark a lot.. take him for more walks and play with him more, take him to dog parks, have play dates or something for him, etc. to prevent him from getting bored. Do all you can to ware him out.