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Cadmium has been identified by the United States Army's Tank and Automotive Command as a threat to worker health and the environment. Based on already completed cadmium substitute testing, an evaluation program was conducted to quantitatively analyze the resistance to vibrational loosening, torque-tension properties, environmentally assisted cracking susceptibility, and corrosion properties of zinc-based alternatives to cadmium, with and without supplemental coatings. The primary performance issues studied were fastener behavior after vibrational joint motion, mechanical performance in corrosive environments, and realistic corrosion performance. Data was generated from various laboratory evaluations and natural marine exposure of fasteners under loaded conditions. Test specimens were prepared by applying electrochemically sacrificial plating layers and supplemental coatings to 1/2-20 UNC Fine, Grade 8 fasteners and 4340 steel tensile specimens.