Apparatuses and methods backward compatible with existing card processing infrastructure are provided to furnish dynamically configurable data to a card reader to facilitate transactions such as credit card transactions. The inventive apparatuses and methods are operable even with card readers configured to read statically implemented data, such as statically implement magnetic stripe data and/or statically printed bar codes. Techniques are also provided to take advantage of features of the inventive apparatus and method to substantially reduce or to eliminate transaction fraud and to improve efficiency for cardholders, card issuers, and intermediary institutions.