3D Secure is a technical standard created by Visa and Mastercard to further secure CNP (Card-holder Not Present) transactions over the Internet.

Mastercard brands their system as 'Mastercard SecureCode' and Visa call theirs 'Verified by Visa'.

3D Secure protects a buyer's credit card against unauthorised use when shopping online. This simple service enables buyers to validate transactions you make over the internet by requesting a personal code (usually sent to your cell phone or email address as a one time PIN). It helps protect against fraudulent use by unauthorised individuals.