The rapid deterioration of aging steel infrastructures requires some significant attention in developing new techniques for effective and economical revival of these structures. External bonding of fiber reinforced polymer (FRP) laminates is a promising method. This book presents a study on performance of FRP-steel joints and steel beams retrofitted with FRP under static and cyclic loading. Experiments on FRP-steel joints and FRP bonded steel beams were performed. A bond failure model was proposed which can be incorporated into numerical modeling to simulate the static behavior of FRP strengthened steel beams with bond failure process. Parametric study was conducted to study the effect of various strengthening parameters on bond strength. The results shuold help shed some light on this new strengthening method, and should be useful to structural engineers, especially to those in fields of structural retrofit and rehabilitation.