This article was written by Sheri Williams and wikiHow staff writer Aly Rusciano. Sheri Williams is a certified dog trainer and behaviorist and owner of sheriwilliams.com, a company that specializes in teaching veterans how to turn their dogs into service dogs or emotional support animals to help them with PTSD. Based in the greater Los Angeles, California area, Sheri has over 20 years of experience in dog training and also runs a general dog training practice that specializes in rehabilitating dogs through booster training techniques. positive. She is certified by the Animal Behavior and Training Association. This article has been viewed 10,370 times.