Abstract: A computer based system that alerts financial institutions (FIs) to undetected multiple debit card fraud conditions in their debit card bases by scanning and analyzing cardholder debit fraud information entered by financial institution (FI) participants. The result of this analysis is the possible identification of cardholders who have been defrauded but have not yet realized it, so they are "at risk" of additional fraudulent transactions. The system also identifies "at risk" cards in the criminal's possession which have not yet been used. The system's early identification of these "at risk" cardholders helps limit losses to individual FIs and the FI community at large. It also provides the coordinated information necessary to the speedy apprehension of the perpetrators.