Each year, millions of dollars are lost due to fraudulent use of
charge and credit cards. Reduce the risk of your business being
victimised by following some basic guidelines.

• Check the overall appearance of the Card.
  Does it look tampered with? Is the signature panel taped or painted
  over with correction fluid or erased? Are there valid dates shown on
  the front of the Card? Ensure that the account number on the front of
  the Card matches the one on the back of the Card, and that they both
  match the account number printed on the receipt.
• Don’t overlook the basics
  Always examine security features on credit cards when accepting them.
  Compare the account number printed on a customer’s card must match the
  account number printed on the sales draft. Also always compare
  signatures when accepting a card for payment.
• Use special care for phone and Internet orders
  When taking orders over the phone, or over the Internet, ask the
  customer for the card expiration date.
  On top of that ask the customer for the Card Verification Value 2
  (CVV2) as part of the authorization process.
  CVV2 is a three-digit security number imprinted on the signature panel
  of Visa cards to help validate the cardholder has the genuine card in
  their possession. If the customer is using an American Express card
  check the Card ID which is a four digit code printed on the face of
  the Card.
• Be aware of the suspicious characteristics of a transaction
  Be alert for transactions by first-time shopper, larger than normal
  orders, orders consisting of several of the same item, orders made up
  of ‘big-ticket’ items, orders shipped ‘rush’ or ‘overnight’, and
  orders shipped to an international address.
• Be aware of the suspicious characteristics of a customer
  Be alert for customers that make several small purchases to stay
  under the floor limit, or ask what the floor limit is or a customer
  that is looking at the Card before signing the Record of Charge. Also
  watch out for customers who purchase a lot of merchandise without
  regard to size, style, colour or price, or those who try to distract
  or rush you during the sale. This type of behaviour could signal card
  fraud.
• Watch out for skimming
  Skimming is an illegal act that helps criminals obtain credit card
  account information through a device to produce counterfeit cards. If
  you see anyone in your workplace using a device that is not part of
  your day-to-day activity, call your company security immediately.
• Use Internet wisdom
  Be on the lookout for purchases where multiple cards are used from a
  single IP (Internet Protocol) address, or those where orders are
  charged to multiple cards but are shipped to the same address - these
  could signal fraudulent activity. Also your business should only
  conduct transactions on the Internet using browser software that
  supports industry standard encryption protocols. Make sure to protect
  systems and data from viruses, and update security software
  frequently.For data maintained on databases or files accessible from the
  Internet, and any data sent across networks make sure that standard
  encryption is used.
• Protect your business and your customers
  Do not store unnecessary track data from credit cards.
  Know your employees. Check references or conduct background checks on
  all your employees. Credit card companies are continuously working to prevent credit card
  fraud, to find out more you can check
  http://www.visa.ca/en/merchant/fraudprevention
  or
  http://www24.americanexpress.com/thailand/en/merchant/manage/reducefraud.asp