OH---I recommend
www.collapsingtrachea.com. They explain the surgical procedure. It is only done on dogs with a severe problem (CLASS III or Class IV). Interesting that glucosamine has not been found to be helpful (but it doesn't hurt either. There is a vet on this site that actually does the surgery, and they have a fund that will pay for the surgery for qualified pets....you have to apply. The surgery is $2000-5000,