When you need to pass someone carrying an umbrella—and you’re going to if you’re carrying a cane umbrella with an effective width of 43 inches on a sidewalk with an effective width of 48 inches—defer to the right. This is key. It’s tempting to thrust an umbrella up or pull it down when passing another umbrella, so as to maintain uninterrupted rain coverage. But do this wrong, and you wind up colliding.