By Jay Dickman
Asking a stranger for permission to take their photograph shouldn't be so hair-raising a prospect. And what if they DO say 'No'? No big deal--"No" probably has been said to you before, so let it roll. It's not life-and-death. Thank them anyway and move on.
I agree with Jay's view--if you approach them with courtesy and express some particular interest in what they are doing or how they look, then the vast majority of people will agree.