A discussion of the various deterioration mechanisms on concrete structures including conventional reinforced structures, post-tensioned structures, and prestressed structures in tropical environments will be presented. Corrosion mitigation systems will be reviewed, and new protection methods will be discussed. Key issues in evaluating the performance of different corrosion protection systems on concrete structures will be described. The effectiveness of the different protection methods for corrosion control used historically will be reviewed. Case histories of both failures and successes of the various methods will be discussed. Cathodic protection systems using impressed current and galvanic designs will also be reviewed, and various limitations and advantages of each method will be presented and compared with other corrosion mitigation systems. A new zinc-hydrogel system for cathodic protection of concrete structures which has been used successfully on reinforced, post-tensioned, and prestressed steel structures will be discussed. The design parameters for the different applications of the zinc-hydrogel cathodic protection system will be described, and the effectiveness of this system will be evaluated based on different operating characteristics for each type of structure. The research data used in developing the zinc-hydrogel material will be presented and compared with actual data from commercial installations to verify the long-term operating characteristics. The cost effectiveness of the zinc-hydrogel system will be compared with other cathodic protection systems as well as other corrosion mitigation systems.