Most metals corrode in seawater. Whether operating, designing or maintaining objects in seawater, understanding basics of corrosion prevention techniques are vital. Several methods exist for protecting metals immersed in sweater. One such method is an Impressed Current Cathodic Protection (ICCP) system. ICCP systems have become more prevalent with modern control electronics. These systems are no longer strictly used on large commercial ships and naval ships. They are implemented on smaller vessels, coastal and offshore structures. A background and overview of modern ICCP systems will be provided and some current real world applications.