B. Anna Su ’00, a passionate leader who headed Model Congress and CityStep during her undergraduate years, died in a drowning accident on Aug. 19 in a relative’s home in Los Angeles, Calif. She was 25.

“Anna was a beacon of hope,” said Jean Su, the younger of her two sisters. “She had an incredible faith in people, in dreams, in things working out.”

“Anna was a tremendous life force, an unbelievable friend, caring and very passionate,” said Scott Taylor ’99, a close friend who worked with Su in the CityStep program. “She inspired the dormant to help others, and she created an enormous amount of energy around her and CityStep.”

Su was born in Taipei, Taiwan, on Aug. 17, 1978.

In 1983 her parents moved the family to the United States. The family moved frequently, finally settling in Potomac, Md., according to Jean Su.

Su was the 1996 valedictorian of Winston Churchill High School, where she served as class president for three consecutive years.

Harvard friends remember Su as a campus leader.

“Anna was one of the most creative, energetic and talented people I met at Harvard,” Adam Kovacevich ’99 wrote in an e-mail. “She had leader written all over her, and she inspired a tremendous sense of loyalty. Anna’s loss is so devastating because the world was clearly a better place with her in it.”

Su served as executive director of CityStep and co-president of Harvard Model Congress. She was also a Crimson editor.

A sociology concentrator in Winthrop House, Su wrote her senior thesis on “the role that husbands play in the lives of high achieving corporate women,” according to Lanhee J. Chen ’99, her fiancé. The two had planned to be married on May 30, 2004.

After graduation, Su went on to work for the Boston Consulting Group in Washington, D.C.

Last fall, she returned to Cambridge, this time attending Harvard Business School (HBS).

According to her sister, Su wanted to go into the fashion industry.

Allen A. Narcisse, a classmate at HBS and personal friend of Su, said that she was a very sweet person, someone who would make unfriendly environments comfortable with the warmth of her personality.

“HBS is a very intimidating place,” said Narcisse. “But the place was more approachable just because Anna was there. She laughed a lot, and you felt great just being around her.”