Without doubt, Dr. Arthur Rosenfeld knew more and did more about energy conservation and efficiency than anyone else in the country. Working out of Sacramento, CA and Washington, DC and prodding his colleagues in the physical sciences, he put many forces into motion to combat waste in energy, whether in buildings, motor vehicles, construction, appliances and many other energy flows that cause excessive pollution and inefficiencies along the way. He succeeded beyond anyone’s expectations, especially in the state of California, which is leading the way at the state level in reducing the amount of energy used per capita and per unit of GDP. His work will live on in homes, businesses, public buildings and everywhere else where fuel is used. Not surprisingly, he was a big champion of solar energy, both passive and active. Tens of millions of people are in debt to him. He was a true public citizen, and a generous one at that, after years as a brilliant physicist at the University of California, Berkeley and before that as a star student of the famous physicist, Enrico Fermi. Condolences to his children.