I like ehbeth's approach, but that would involve more time than I am willing to commit to a panhandler. Usually I give them a buck or what spare change I have in my pocket and move on.
I won't give them anything if they are agressive.
When I was 16, I travelled from Long Island to NYC to secure my first passport. I had to get to the Pan Am building, but had no idea where it was. When I came upon a young women asking men in suits for spare change, I told her I would give her $2 if she would give me directions to the Pan Am building.
She told me she was leaving this corner anyway and would take me to the building herself as it was along the way to where she was going. We talked as we walked and I asked her if she panhandled on a regular basis or just when she needed a few bucks. She told me it was her regular "job" and that she made close to $20,000 a year at it. This was in 1971.
When we reached my destination she told me to keep my $2 and wished me good luck. Several years later 60 Minutes did a piece on professional panhandlers in NYC and featured a guy from the New Jersey suburbs who lived in a nice house and commuted to Manhattan everyday to ply his trade. He claimed he was making something like $40,000 a year.
Just last week my wife and I drove from La Guardia to upstate NY. We got stuck in a crawling traffic jam in the Bronx and witnessed two beggers battle for what I guess was a primo spot for panhandling. The traffic was due to ramp construction and so I'm assuming it was a daily jam that the beggers could count on. They both were walking in between the barely moving cars holding cardboard signs that referenced their homelessness and hunger. Both seemed relatively young, and were filthy. Both were wild haired and wild eyed and both walked with limps. In fact they looked like they could be brothers, and for all I know, maybe they were.
When the taller of the two spied the other approaching, he started to yell and gesture angrily. The smaller one grinned and shouted back at him, only to quickly shuffle away when the one with apparent territorial rights came at him with a raised table leg. Because we were pretty well stuck, we got to watch the scene play out for a while.
Fortunately, the two never actually came to blows but there were a lot of threats, a lot of cursing and even a few thrown objects. Eventually the smaller of the two must have decided he wouldn't be able to drive the other off ( it was clear that there would be no sharing of the turf) because he scuttled across the highway and sort of jumped and rolled over a barricade, to be seen no more.
Neither of them got money from anyone and I would have not rolled my window down for either of them even if they had not been at war. I can't say what they wanted money for, but I'm sure they weren't professionals and I would be surprised if it wasn't for drugs or booze.
A sad experience that led to speculation about their lives and no good ideas about what society could or should have been doing for this pathetic pair.
I seriously doubt that giving them money would have been of any real help to them, but if they had approached me while I was walking and had saved their aggression for each other, I probably would have tossed them a couple of bucks. I know though that it would not have made me feel good to do so; it never does.