Joseph R. Gunn III, board chairman from 2001 to 2008 of Robert R. Nathan Associates, an international economic consulting firm, died June 5 at Suburban Hospital in Bethesda. He was 84.

The cause was lung cancer, said his wife, Marie Gunn.

Mr. Gunn spent his early career in San Francisco as an economic analyst and statistician with Standard Oil of California and the Asia Foundation, where he became a top adviser to the royal government of Afghanistan.

He settled in the Washington area in 1967 when he joined Nathan Associates.

His expertise was in development economics, industrial organization, international trade, and petroleum economics, and his work took him to Central and South America, Africa, the Middle East and Asia. In the mid-1970s, while still working at the firm, he was a resident senior economic adviser in Thailand.

He also had served as a senior vice president and director and treasurer of the Robert R. Nathan Memorial Foundation.

Joseph Ridgeway Gunn III was a native of Ross, Calif. He was a 1954 business administration graduate of the University of California at Berkeley, where he also received a master’s degree in economics in 1958.

In 1967, he did graduate work in international trade and development economics at Nuffield College of the University of Oxford in England. He also lectured there on economic development, multinational trade and intraregional trade settlements.

He was a past president of the Cosmos Club in Washington, and his memberships included St. Francis Episcopal Church in Potomac, Kenwood Golf and Country Club in Bethesda and the Asia Society. He was a Potomac resident.

Survivors include his wife of 61 years, Marie Thurlow Gunn of Potomac; three daughters, Dana Winslow of Washington, Anita Shirley of Chapel Hill, N.C., and Janice Smeallie of Alexandria; and five grandchildren.

— Adam Bernstein