Current Techniques for identifying microbially influenced corrosion (MIC) involve a battery of chemical, electrochemical, metallurgical, and microbiological tests. The most common method for detection and evaluation of microbial activity employs plate or tube culture technique. These methods are expensive and time consuming yielding results that may not be truly representative of the consortia of microorganisms involved in MIC. Consequently, significant damage has already occurred before MIC is identified which makes effective treatment difficult resulting in enormous economic losses. Early detection is crucial, so that corrective measures can be promptly and effectively instituted. The objective of this proposal is to identify specific protein markers that correlate with initiation and progression of MIC. Data obtained will from the basis for development of a rapid and economical diagnostic procedure for MIC.