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C ORROSION is an extremely costly problem for industries and business sectors throughout the world and results in severe economic impact. In 1998, Congress funded the Department of Transportation and the Federal Highway Administration to estimate the total cost of corrosion on theU.S. economy and provide corrosion prevention guidelines. The final results of the survey estimated the extrapolated total direct corrosion cost to be $278 billion per year, which is 3.14%of the gross domestic product in theUnited States [1]. In 1996, the U.S. spent $1.7 billion on commercial aircraft maintenance and lost $0.3 billion due to corrosion downtime [2]. The “find it and fix it” maintenance practices of the airline industry are costly and, in some cases, inadequate. The present note will focus on identifying a detection method for the galvanic type of corrosion that plagues aircraft. Many techniques exist for detecting corrosion in aircraft; however, these methods are typically inadequate due to the intrinsic human error present and are difficult and time-intensive to implement. Two general categories of corrosion monitoring techniques exist, nondestructive evaluation (NDE) and structural health monitoring (SHM). NDEmethods include techniques such as visual, eddy current, ultrasonics, electrochemical impedance spectroscopy, color visual imaging, radiography, and infrared imaging [3]. The second class of detection is SHM and is typically superior due to the automated nature of the sensing system. Examples of SHM systems used in aircraft include the monitoring of pH and humidity, acoustic emissions, ion concentration, and chemical potential detectors. The present study will provide results on a series of tests performed using piezoelectric-based impedance techniques, which are a newer and less developed method of performing SHM. These methods use the electromechanical coupling present in piezoelectric materials to determinewhen structural changes have occurred.When the piezoelectric material is bonded to the structure, its electrical impedance is coupled to themechanical impedance (a function of the mass, stiffness, and damping) of the structure, providing a means for characterizing it. As damage occurs or progresses, the electrical impedance measured from the piezoelectric materials shifts, which can be quantified using statistical methods, providing a method of measuring the damage present. For a detailed review of the impedance method and it application see Park et al. [4] However, the ability to use this technique to measure the small changes associated with the onset of corrosion has not been identified. This note will experimentally evaluate the use of piezoelectric materials in conjunction with the piezoelectric-based impedance method to detect, locate, and quantify precrack surface corrosion damage. The impedance variations caused by changes in corrosion location, pit depth, and surface coverage will be correlated to the damage metric, which is calculated from the measured impedance signatures.