About 6:05 p.m. central daylight time on Wednesday, August 1, 2007, the eight-lane, 1,907- foot-long I-35W highway bridge over the Mississippi River in Minneapolis, Minnesota, experienced a catastrophic failure in the main span of the deck truss. The NTSB investigation identified the cause of the collapse and many design and inspection issues. This case study in engineering ethics examines the history of the bridge and the subsequent NTSB investigation of the failure, including recommendations, and assignment of damages to the parties involved. The session will also consider related ethics cases.