The departure of John F. Kennedy Jr.’s single-engine turbo plane on July 16 from a small New Jersey airport marked the end of a long day for Lauren Bessette. An investment banker in the corporate finance division of Morgan Stanley Dean Witter & Company, Ms. Bessette had gotten caught in traffic en route from her office at 1585 Broadway. She was still wearing a beige work dress as she walked the tarmac to Mr. Kennedy’s Piper Saratoga 32.

Lauren Bessette, an older sister of Mr. Kennedy’s wife, Carolyn, started as an analyst at Morgan Stanley in 1987, a year after her graduation from Hobart and William Smith College. In 1989, she left Morgan Stanley to attend the Wharton School of Business at the University of Pennsylvania. After receiving her M.B.A. in 1991, it was back to Morgan Stanley.

“She was very professional,” said one former Morgan Stanley executive who worked with Ms. Bessette in the early 90′s. “At that time, most of the women who really came across well were typical career women–meaning, very, very much focused on the career, really trying to kick ass. She was much more balanced.”

“She was an unusually attractive woman,” said another colleague. “She was really kind of a knockout. I thought she was beautiful, and I was just struck.”

Ms. Bessette graduated from Greenwich High School in 1982. At Hobart and William Smith College in rural Geneva, N.Y., she majored in economics. Her teachers said she was assiduous.

“You would like to have a roomful of Laurens,” said Prof. Daniel McGowan, who gave her an A for her work in Monetary Theory and Policy, a course he believes piqued her interest in Wall Street. “She was definitely honors material. But she was fun to have in class, because she was interested in the subject, wanting to learn, not afraid of entering something that had been sort of male-dominated.”

Ms. Bessette, who died at 34, grew up with sisters Carolyn, one year her junior, and Lisa Ann, her identical twin, in Greenwich, Conn. Her father, William Bessette, is an architectural engineer, and her mother, Ann, is a teacher and administrator. When the Bessette girls were young, their parents divorced. Afterward, Ann married Richard Freeman, an orthopedic surgeon. The Freemans now live in Old Greenwich, Conn. Mr. Bessette lives in White Plains, N.Y. The family has requested minimal coverage of the tragic deaths of their daughters.

In 1994, Lauren Bessette opted for a four-year stint in Morgan Stanley’s Hong Kong office. There, she helped execute capital-markets transactions. During her time there, in 1996, Morgan Stanley promoted her to vice president.

“It was hard on single women,” said another firm source, who knew her in Hong Kong. “It’s very family-oriented; most people who go out there are married. In a way, it’s a hardship, because it doesn’t make it any easier for them to find somebody to marry.”

Her twin sister, Lisa Ann Bessette, has taken a somewhat different course: After graduating from the University of Michigan, she is reported to have been pursuing a doctorate in Renaissance studies in Munich.

In February 1998, Lauren Bessette returned to Morgan Stanley’s Manhattan offices and in December was promoted from vice president to principal, a job title one level below managing director in the company hierarchy. She spent her days pitching investment ideas to the firm’s major private equity clients. Soon after her promotion, she agreed to buy a $925,000 artist’s loft at 17 White Street, a few blocks from the converted warehouse on N. Moore Street where sister Carolyn had lived since her marriage to Mr. Kennedy in 1996.

Ms. Bessette was reportedly seeing film and television producer Bobby Shriver, 45, the son of Sargent Shriver and Eunice Kennedy Shriver, aunt and uncle of John F. Kennedy Jr. Sources close to the family say Bessette was on her way to visit Mr. Shriver on Martha’s Vineyard the night of July 16. The couple would have stayed the weekend at the Kennedy-Onassis retreat near the town of Gay Head.

Carolyn Bessette and John Kennedy lived surrounded by the media; their deaths have been much noted. To those who knew Lauren Bessette, there seems to be something incongruous about that; she wasn’t famous, but she was an accomplished woman, toughing it out and enjoying herself in a male-dominated field. One former colleague, freshly familiar with the tragic news, said: “She may have been more successful than they were.”

Lauren G Bessette