An electronic transaction payment system is provided having a vendor terminal associated with a vendor who provides goods or services to a purchaser, a vendor smart-card and a vendor smart-card reader for transmitting data to and receiving data from the vendor smart-card. The system also includes a purchaser smart-card reader which is connected to the vendor terminal and which is operable for transmitting data to and receiving data from a purchaser smart-card. In operation, payment for goods purchased by the purchaser is made between the purchaser smart-card and the vendor smart-card. In a preferred embodiment, the payment data is encrypted using an encryption key specific to the transaction between the purchaser and the vendor. A third party registry terminal may also be provided for providing validation of the vendor and/or the purchaser.