Heat straightening has been used to repair damaged steel structures for many years. However, until recently practitioners use of the method was based on experience gained through trial and error. Recent research had provided and engineering basis for the method and established procedures for its use. The engineering and construction community has been hesitant to utilize heat straightening for several reasons including: past misuse of the process which has produced fractures during repair; concerns about the effect of heat straightening on material properties, especially ductility; and a general lack of understanding of the method. Its current application is primarily in repair of damaged bridge girders with limited application for other types of construction. Even though a scientific basis now exists for the method, there is a major gap in available data that has limited the application of heat straightening. There have been no significant investigations into the fracture sensitivity of heat straightened members. Without this knowledge, a performance based design approach cannot be used for designing heat-straightening repairs. The purpose of this proposal is to describe a research plan that will quantify the process and define the limiting parameters for a successful repair.