"We're all devastated, but especially the people in her department," said spokeswoman Martha McKinley. "She was very well-liked and respected."
Gronlund, who joined BMW in 1990, was traveling on vacation, McKinley said.
In addition, Anna Allison, a contract worker for Toyota Motor Sales U.S.A. Inc.'s information systems department, was aboard American Airlines Flight 11 from Boston to Los Angeles, the first plane to crash into the World Trade Center.
Allison, 48, lived in Stoneham, Mass., and was president of A2 Software Solutions Inc., a software development company in the Boston area. She was going to visit clients in Southern California.
Said Toyota spokesman Joe Tetherow: "She was a good friend and a valuable co-worker to those who worked with her."