These puppies are generally taught to be mellow (they are not given attention when they act excited, etc.)

I just want to clarify that it's incorrect to say these puppies are "taught to be mellow". That's a personality trait that is sought for service dogs, you can't teach it. You can reinforce behavior by not giving attention to it - in the same way you would ignore tantrums in a child. But, you can train a high energy dog to be well behaved but you can't train him to be a mellow dog.

There are also dogs that don't make it through law enforcement training. Friends of ours have a dog who received a lot of training but "flunked out" the program to be a federal customs drug-sniffing dog. They're all trained somewhere in VA, I think. One spouse is in law enforcement so that's how they got the dog; not sure if these dogs can be adopted by the general public.

Anonymous wrote:There are also dogs that have been trained by prisoners.

Virginia has this program at a number of state prisons. It's a great program -- you can get info at: http://vadoc.virginia.gov/offenders/institutions/programs/penpals.shtm