At 38, Karen Joyce Klitzman had seen more of the world than any 10 people do in a lifetime. After Princeton, she taught for several years in Macao, near Hong Kong. Living in a house wedged between a pig farm and a brothel, she escaped to Hong Kong on the weekends. Then she taught English in Beijing, where she lived in a hovel with a suspicious landlady, and where a bicycle ride to the public bathhouse was a luxury. "It was a completely exotic environment," said Joan Klitzman, her mother. "So far removed from the Upper West Side, where we lived."

After graduating from the Columbia University School of International Affairs and Public Policy, she began working at the New York Mercantile Exchange. An energy specialist, she traveled in Siberia and throughout the Middle East. Recently, she started at eSpeed , a division of Cantor Fitzgerald.

She was quick-witted and played a crackerjack tennis game, said Donna, her twin sister, a New Jersey doctor. "Like having a built-in best friend."

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