From 1991 to 1992 he was the J. Herbert Holloman Fellow at the National Academy of Engineering in Washington, DC.

From 1995 to 1997 he was Director for Energy and Environmental Systems at Lawrence Livermore National Laboratory, on temporary assignment from his position as Research Vice President, Technology and Environment, for AT&T.

From 1997 to 2004 he was the Environment, Health, and Safety Vice President for AT&T, with global responsibility for those operations for the firm.

In 2007 he was President of the International Society for Industrial Ecology; Chair of the AAAS Committee on Science, Engineering, and Public Policy; a Batten Fellow in Residence at the University of Virginia's Darden Graduate School of Business Administration; He is a member of the Virginia Bar, and has worked as an attorney for the Civil Aeronautics Board and the Federal Communications Commission, as well as a strategic consultant on economic and technical telecommunications issues.

He has taught courses on industrial ecology and design for environment at the Yale University School of Forestry and Environmental Studies, the University of Virginia School of Engineering and Applied Science, and at the University of Wisconsin Engineering Extension School; and has lectured widely on earth systems engineering and management, industrial ecology, design for Environment, and the social and policy implications of emerging technologies, especially information and communication technologies.