In this lecture given at Stanford University, Amory Lovins presents his theories on sustainable development. He argues that the efficient use of energy is a fundamental driver of sustainable development because it is part of the proper allocation of financial capital on the scale of the macroeconomy. Lovins provides several examples of the ways in which companies have created energy efficient, money saving products. He also provides case studies of solutions to development challenges. Some of these solutions include plugging needless leaks of money out of the local and national economy; substituting efficient use and local resources in order to help businesses survive downturns; helping local businesses to modernize, diversify, and expand before seeking new ones; and nurturing local startups that will meet local goals; and recruit outside businesses in a smart way that advances the community’s goals and yields net benefits, not just gross benefits.