Angela Simon was 24 years old when she was told to leave a meeting.

 It was 1988, and it was her first year working as a project manager for Menlo Park, California-based Western Allied Corp. She was assigned to a project in downtown San Francisco for a five-story building. Steel beams had just gone up on the site, so the project superintendent called for a coordination meeting. Simon recalled walking into a tiny trailer with her supervisor and the room being packed with steelworkers who were talking among themselves — until they noticed Simon, that is.