Strengthening and rehabilitation have been widely implemented for many years to extend the service life of reinforced concrete structures. The paper begins with a comprehensive review of the fiber-reinforced polymers (FRP) utilization on strengthening particularly over the traditional materials formerly used in practice with respect to materials, manufacturing, operation, construction, and maintenance phases, as well as the engineering and environmental performance of such materials. Carbon and Glass FRP, the most frequently used strengthening materials, are particularly designated in the study and are employed to conduct an environmental performance evaluation using the previously published data in the literature. The paper then investigates the punching shear strength of flat slab-column connections strengthened with externally bonded FRP by means of a nominated database comprising 57 number of data points harvested from the recent literature. The database is used in the evaluation of the test data with TS 500 code equations and the recent modification of Chen and Li. The study enabled the key factors affecting the punching shear strength of such connections to be emphasized and highlighted the fact that the TS 500 code equations fall conservative in predicting the punching shear strength of slab-column connections strengthed with FRP. The study is novel as it provides a comprehensive review of the FRP as a strengthening material with regards to environmental sustainability and also provides an insight into the structural implications of this material by evaluating the current TS 500 code provisions and recent modifications.