Gil Masters works on energy efficiency and renewable energy systems as keys to slowing global warming, enhancing energy security, and improving conditions in underserved, rural communities. Although officially retired in 2002, he continues to teach CEE 176A: Energy-Efficient Buildings, and CEE 176B: Electric Power: Renewables and Efficiency. He is the author or co-author of nine books, including Renewable and Efficient Electric Power Systems, now in its 2nd edition (2013), Introduction to Environmental Engineering and Science, now in its third (2008) edition, Energy for Sustainability: Technology, Policy and Planning (2008). Professor Masters has been the recipient of a number of teaching awards at Stanford, including the university's Gores Award for Excellence in Teaching, and the Tau Beta Pi teaching award from the School of Engineering. Over the years, more than 10,000 students have enrolled in his courses. He served as the School of Engineering Associate Dean for Student Affairs from 1982-1986, and he was the Interim Chair of the Department of Civil and Environmental Engineering in 1992-93.