Abstract: At approximately 4:30 p.m. on December 20, 2012, in Chippewa Falls, WI, an employee was fatally injured when a recently-poured concrete wall collapsed, killing him and trapping three other employees. The three other employees were transported to the hospital with critical injuries. All of the injured employees were employed by Lewis Construction, Inc., the concrete subcontractor. The wall that collapsed was 10 ft. high, 28 ft. long and 10 in. wide. At the time of the collapse, the four injured employees were working from an elevated walkway attached to the west side of the formwork. The employees were exposed to struck-by hazards, as the formwork for the cast in place concrete wall was not adequately braced. There was a light snowfall and the temperature was approximately 19 degrees Fahrenheit when the accident occurred. Injuries of the three hospitalized employees included broken bones, leg, back and neck injuries. The fatally injured employee suffered compression injuries of the chest and head.