This is a new comprehensive methodology to analyze the lateral stability of long slender bridge girders. Technology has enabled the manufacture of increasingly longer girders. Slender girders present a lateral stability concern. Each stage of a girder's transition from the casting bed to its final location in the bridge is considered. These conditions include when handling from the top with embedded or attached devices and supported from below during storage, transit, or in various conditions on the bridge during construction. These recommendations are the result of ground-breaking research conducted by Robert Mast in the 1990s. In 2007, the PCI Committee on Bridges clearly saw the need to address girder stability. They selected a specialized team to develop these recommendations. The producer members of the team have contributed substantial practical field experience. Together with a large number of designer practitioners, the team has developed an industry consensus recommended practice that provides methods to calculate the factors of safety during each of several stages of a girder's life. This is a must have publication for all stakeholders in bridge design, fabrication, and construction.