Andrew Ruben and Jib Ellison of Wal-Mart Stores, Inc. share their experience of transforming the largest company in the world into an environmentally sustainable business.

Patagonia Inc. founder Yvon Chouinard characterizes himself as a reluctant business man. Nevertheless, he offered a slew of counterintuitive business tips during the 2006 Von Guegelberg Memorial Environmental Lecture at the Stanford Center for Social Innovation.