Secure payment card transactions

A method of securing payment card transactions at a point of sale (POS) in a payment card processing system, the system comprising a POS terminal (30) and a POS server (36) in communication with the POS terminal over a network, the POS terminal (30) comprising a host computer (34) and a card input device (28), the host computer having a POS terminal application (38) and a POS security layer (40) installed therein, the POS server having a POS server application (46) and a security application (48) server installed therein, the POS server application (46) in communication with the POS terminal application (38) to process payment card transactions, the server security application (48) in communication with the POS security layer (40) through a secure channel (44) in the network, the method comprising: the POS security layer (40): intercepting data actual payment received from the card input device when a user initiates a payment card transaction whereby the actual payment data is prevented from reaching the POS terminal application (38); and sending the actual payment data to the server security application (48) through the secure channel (44); the server security application (48): receiving the actual payment data from the POS security layer (40) through the secure channel; generate false payment data by replacing all or a portion of the actual payment data with false payment data; and transmitting the false payment data through the secure channel (44) to the POS security layer (40); the POS security layer (40): receiving the false payment data from the server security application (48) through the secure channel (44); and pass the false payment data to the POS terminal application for use in place of the actual payment data; the POS terminal application (38): receiving the false payment data from the POS security layer (40); and transmitting the false payment data over the network to the POS server application (48); the POS server application (46): receiving the false payment data over the network from the POS terminal application (38); processing the false payment data as if it were real payment data whereby the false payment data is stored in a database (50) instead of the actual payment data; and transmitting the false payment data to the server security application (48) for payment processing; the server security application (48): receiving the false payment data from the POS server application (46); and using the false payment data to process the payment card transaction by transmitting an authorization request to a payment gateway (52), the authorization request comprising the false payment data and the actual payment data.