They can be valid for a relatively brief time, and restricted to the actual amount of the purchase or a limit set by the client. A lost or stolen card can be cancelled, and if this is done rapidly, will greatly confine the fraud that can take place in this way. European banks can require a cardholder's security PIN be entered for face to face purchases with the card. It's currently regular practice to just ship to affirmed addresses as a safety effort to limit fraudulent purchases. Controlled payment numbers (also known as virtual credit cards or disposable credit cards are another alternative for ensuring against credit card fraud where presentation of a physical card is not required, as in phone and web based purchasing. A few merchants will accept a credit card number for in-store purchases, whereupon access to the number allows easy fraud, however many require the card itself to be available, and require a signature.