Henry Ehrenreich, a popular and widely praised researcher, mentor, and educator at Harvard, embarked on his first major journey alone, at the age of 11 in the summer of 1939. He left Frankfurt via the Kindertransport, a mission to rescue Jewish children by moving them from Nazi Germany to safe havens in England. After twenty months and many adventures, Henry and his parents, who fled separately from Germany later that summer, were reunited in the United States, eventually establishing a new life in Buffalo, New York.

A pioneer in semiconductor materials and a Harvard professor for more than four decades, Ehrenreich, Clowes Professor of Science, Emeritus, died on January 20, a few months before his 80^th birthday. He also served as the University's first Ombudsman and extended his academic interests to government and public policy, spending a year working with the Director of the Office of Science and Technology Policy at the White House and serving on several national and international panels.

"An enormous number of colleagues, friends, and students at Harvard and throughout the world have benefited from their interactions with Henry as well as from the papers and reports he wrote, and the volumes he edited. His insights, wisdom, and thoughtfulness will be sorely missed," said Paul Martin, John H. Van Vleck Professor of Pure and Applied Physics at Harvard.

Ehrenreich received his B.A. (1950) and his Ph.D. in the emerging field of semiconductor physics (1955) at Cornell, where he also met and married Tema, his wife for almost 55 years. He spent the next eight years at the General Electric Research Laboratory in Schenectady, NY, then a hub for scientific research. In 1963 he was appointed a professor in the then Harvard Division (now School) of Engineering and Applied Sciences.

"Over the course of his academic career, as the flood of uses of semiconductor devices continued to grow, he published roughly 200 papers," said long-time collaborator Peter Pershan, Frank B. Baird, Jr. Professor of Science. "He was a master at understanding, explaining, and predicting the electronic and optical properties of the ever more complex ingredients of these devices through detailed calculations and reliable insightful approximations."

In addition to educating and mentoring students in his research specialty, Ehrenreich developed courses for students at all levels that covered topics ranging from the physics, chemistry, and policy aspects of materials and devices to energy and the environment to even ones that touched on his personal interests of history and music. Ehrenreich, a skilled pianist, developed his love for music early thanks to his father, a choral conductor and music critic.

At Harvard, he did much to promote and improve undergraduate education in science and engineering, chairing the Science Center Executive Committee and the Core Committee on Science from 1987-1999. As Director of Harvard's Material Research Laboratory (now the Materials Research Science and Engineering Center) from 1982-90, he fostered strong and enduring collaborative interdisciplinary courses and research programs.

More broadly, Ehrenreich influenced the materials science field as the editor or co-editor of over 30 volumes of /Solid State Physics/, a renowned and widely consulted annual review of major advances in solid state science and technology. He served on and chaired numerous national and international committees including the Solid State Commission of the International Union of Pure and Applied Physics for ten years and the Department of Defense's DARPA Materials Council for twenty.

As an expert in semiconductors, Ehrenreich was asked to assess solar photovoltaic cells; he headed the American Physical Society's Study Group on Solar Photovoltaic Energy Conversion from 1977-81 and served on the Department of Energy's Photovoltaic Advisory Committee. As concerns about pollution and climate change heightened, he spent more time studying and teaching also about the science and the economics of alternative sources of renewable energy, most notably, wind.

In addition to his wife, Tema, Ehrenreich leaves a daughter, Beth, two sons, Paul and Robert, and ten grandchildren.