Abstract: A technique for representing behavioral patterns indicating fraudulent electronic cash transactions through micro-dynamic simulation of an electronic cash transaction system implementable using smart cards with embedded microcomputers. The electronic cash transaction system is stochastically modeled by four categories of agents corresponding to the participants in an electronic cash transaction economy. Some categories of agents are further subdivided into segments that have different characteristics, including the circle of other agents with whom they regularly conduct electronic cash transactions. Agents with counterfeit or fraudulent smart cards may form a segment in the simulation to allow the effects of the counterfeit or fraudulent electronic cash transactions in the complete system to be observed.