Mark Nelson, PhD, takes us on a global expedition to learn how we are wasting the world's dwindling supplies of fresh water by flushing away a very valuable resource, our own human wastes A founding director of the Institute of Ecotechnics, Dr Nelson has worked for several decades in closed ecological system research. As one of eight brave souls enclosed in the pioneering Biosphere 2 experiment, he realized how essential the proper re-use of human waste is to the health of the planet. This led to what Dr Nelson calls a life-long love affair with constructed wetlands, where he discovered an important solution to some of our trickiest global dilemmas: Wastewater Gardens.