The paper outlines the history of innovative ASTM specification for corrosion resistant steel and GFRP bars for concrete reinforcement. A review of the mechanical properties of steel vs GFRP rebars will be presented along with the design codes and tools that are available for engineers. Extensive design examples utilizing the ACI and AASHTO codes will be presented along with a thorough evaluation of the carbon footprint (EPDs) for all the reinforcing products.