Print this out and leave it at the neighbors as a hint. Petsafe
My wifes Pomeranian just in the last year has developed the nasty habit of non stop barking when let outside, we bought this and it works like a charm. The only time the dog will even yelp now is when there is a true threat such as a raccon, skunk or other wild animals venturing into the yard.

A computer once beat me at chess, but it was no match for me at kick boxing.