Cathodic protection is an electrochemical means of corrosion control in which the oxidation reaction in a galvanic cell is concentrated at the anode, which suppresses corrosion of the cathode in the same cell. This article provides a detailed discussion on the fundamentals and types of cathodic protection as well as their power sources and design considerations. The criteria for the cathodic protection and types of materials used in sacrificial anodes and impressed-current anodes are also discussed. The article provides examples selected for familiarizing the design engineer with the steps for selecting a specific corrosion control method.