It is fine to smile and make a short comment to the handler about their dog such as what a nice looking dog they have.
Do not try to stop the handler while they are going about their shopping or attending to business. Would you do this to someone without a dog?
If you are in a situation where speaking would be a normal course of events then it is fine to ask a question about Assistance Dogs in general.
Do not ask ask personal questions of the handler such as what is their disability.
If the handler does not wish to speak about their dog or hold a conversation do not be offended. They may be having a bad day, may have their mind on personal matters, tired or not feeling well – just like anyone else.
Do not try to get the dog’s attention by calling to it.
There is no reason to touch or pet the dog – it has a job to do.
Do not try to give a treat to the dog.
If you have your dog with you and are near an Assistance Dog Team, do not let your dog try to interact with the Assistance Dog either by trying to play with, bark, or make eye contact with the Assistance Dog.
If you are near a visually impaired handler and you have your dog with you, let the handler know of your location such as you are passing them or sitting near them.