Putting your money where your mouth is, if your mouth happens to enjoy granola and free-range, sustainable goat's milk.
Green investing involves putting money into companies that create environmentally-friendly products and services. Or, at least, it involves judging companies by their environmental practices, only investing in those that have high standards regarding their carbon footprint.
So...a green investor would stay away from Toxic Sludge Dumper Inc. and concentrate their interest on firms like Solar, Wind, and Rainbow Capture Co. or Putt-Putt Electric Car Mfg., LLC.