[Cagdu] What's the best sign for a dog's harness?

[Fred's Web]

Hi all,

Do you have a sign on your dog's harness?
What does it say?
Does it do any good?  

I'm asking because I do not have a sign on Churchill's harness.  His harness has a blue and white "Guide Dogs for the Blind" logo on the white harness.  I thought that would've been enough, but I have to almost beat the public away.  

I'm thinking that we really need some kind of sign.  If you have one, what works for you?  If you don't, how do you keep the public at bay?

Thanks,
Fred & Churchill