John C. Sawhill; Head of Nature Conservancy

John C. Sawhill, who as president of the Nature Conservancy led the world’s largest private conservation organization through a period of unprecedented growth, died Thursday at a hospital in Richmond, Va. He was 63 and had diabetes.

Sawhill, an economist, business consultant and energy administrator for three presidents, knew his way around boardrooms and had headed New York University, the country’s largest private university. He applied the financial deal-making of large corporations to the preservation of environmentally sensitive marshes, barrier islands, coral reefs and ranchlands through land trusts that restrict uses.

During his tenure, conservancy officials said, the organization bought property and brokered other sales that helped protect more than 7 million acres in the United States. The organization tripled its staff to 3,000, doubled its membership to 1.1 million and increased its revenues from land sales more than fivefold.

Just two weeks ago, the conservancy announced the $37-million acquisition of Palmyra Atoll in the Pacific Ocean.

Sawhill, who was president of New York University in the late 1970s, was a familiar figure in government circles, having served in Washington during the Carter, Nixon and Ford administrations.

He had been deputy energy secretary; chairman of U.S. Synthetic Fuels Corp.; administrator of the Federal Energy Administration, and associate director for natural resources, energy, science and environment in the Office of Management and Budget.

Under his leadership, the Nature Conservancy moved away from its traditional purchases of individual, unique areas considered in need of protection. Sawhill said early on that national park and conservation-area boundaries would prove useless against the encroachment of development.

He said the traditional approach of setting aside areas in parks created “lifeboats of natural diversity. But even lifeboats can sink. Noah’s Ark has sprung a leak.”

“The fundamental way that we protect the environment, frankly, is to buy it,” he often told audiences. In Sawhill’s view, that also meant retaining the right to help oversee logging and other uses on land the conservancy bought and resold.

In 1995, the conservancy undertook a major fund-raising effort, taking in $315 million for its Last Great Places campaign, which aimed to protect entire functioning ecosystems. In March, Sawhill announced the start of a $1-billion campaign to help protect 200 “ecologically significant ecosystems” in the United States and abroad.

Sawhill, described by the New York Times as a man ascetic in behavior and diet, was born in Cleveland and raised in Baltimore. He graduated from Princeton University and received a doctorate in economics from New York University.

He taught at NYU and was assistant dean before being named president in 1975. He led a campaign that raised $150 million for the university, achieving an academic and financial turnaround that was later called one of the “miracles of higher education.”

After his federal service, he headed the energy consulting practice of McKinsey & Co., directing strategic planning studies for energy companies. He wrote books and articles on energy use and conservation.

Survivors include his wife, Isabel V. Sawhill, a senior fellow at the Brookings Institution; a son, James W. Sawhill; a brother; a sister; and a grandson.