This invention is a comprehensive “Dynamic Security Code” (“DSC”) System (“DSC System”) that can change the security code of a prepaid, debit, or credit card (“Payment Card”). In an effort to thwart Card-Not-Present (“CNP”) fraud, the DSC System provides dynamic security code values (“DSC Values”) that have a limited use. The DSC Values provided by this DSC System can be calculated by various methodologies and can be used within existing standard payment card infrastructures. The DSC System can also be used with other form factors and in other environments not related to payments such as balance inquiries. The DSC Values can be calculated by a DSC Generator Server or on the card itself.