Abstract: On November 13, 2007, Employees #1 through #3 were installing 66 ft long wooden trusses connected by metal plates in a post frame building under construction. They were working from the trusses, installing purlins that were being handed up from the ground by a coworker. Seven of the trusses, which were spaced every 9 ft, had been installed. Temporary bracing included bracing of the first truss by attaching it to the wall and two rows of bracing to the ground. The first and second trusses had two rows of X-bracing installed between the bottom and top chords. Each truss had two rows of bottom chord bracing and several purlins were installed on the top chord. As the employees were working, the wind speed started to pick up and the crew began installing all of the purlins on the top chord, which were spaced every 2 ft. All but three of the purlins had been installed when there was a large gust of wind. Seconds later, one of the braces connecting the end wall to the first truss broke, and a few seconds after that, the truss system shifted and collapsed to the ground. Employees #1 through #3 fell to the ground with the trusses. All three sustained fractures and other injuries; Employee #1 was hospitalized and Employees #2 and #3 were treated and released. Wind gusts in the area were measured at 25 mph, but the topography may have increased the speed at the site. Additional temporary truss bracing, especially diagonal top chord bracing should have been installed.