Abstract: A system for transferring data between persons, for example in lieu of cash transactions, requires that each person to or from whom data is to be transferred carries a portable electronic device including a memory. Data transfer means in the form of data recording devices are provided at fixed locations which cooperate with the portable electronic devices to transfer data into or out of the portable electronic devices. Preferably both functions may be effected at each location. Data taken from a portable electronic device may be recorded in another portable electronic device for transfer elsewhere. The portable electronic devices may be in the form of flat cards in which logic microstructures are encapsulated.