I give a regular class on Dr. David Johnstone's elective for master's students that looks, inter alia, at water infrastructure. My brief is to ensure that the class has a reasonable understanding of the basics of finance - the difference between equity and debt, what WACC means, that sort of thing. Electives in any geography department probably convene a pretty wide range of backgrounds, and ours is no exception. Usually, this group ranges from folk who have had no exposure to corporate finance, through to people with a nodding acquaintance of key terms. This year... we have a chap who is CFA qualified. He was decent enough to sit pliantly through my presentation, but there was understandable pain and befuddlement in his eyes. I am very grateful to him for coming to the front and writing out an equation that illustrated a point much more effectively than my somewhat rambling attempt. But on balance, classes where I can pretend to wield a financial mystique are far easier.