I was on a bridge in Boston and I noticed how strong the shadows were on the ground from the metal uprights; but, the image looked empty without another element so I kept shooting other shots. I happened to look right to see if I was blocking the way and a woman was coming my way with this b&w patterned dress! I turned left and focused on the shadows until she came into my frame. It was happenstance and just what I needed to make a better photo. I'm glad she volunteered!