When a thief gathers enough information about you to pretend to be you, that's called identity theft. It doesn't take much of the right kind of personal information (for example, your Social Security number, address, mother's maiden name, or bank account number) before the thief can cash in on your government benefits, make purchases on your credit card, open bank accounts, take out loans-even commit crimes-all in your name.

Think about places where a thief might steal personal information:

• Your wallet, of course. More valuable than any cash are your driver's license and other cards such as your health insurance or credit cards. Did you note your personal identification numbers (PINs) on a scrap of paper? Is your Social Security number on any cards you carry?

• Your mailbox. An unlocked mailbox is an open invitation for anyone to take a credit card bill or bank statement with your name, address and account numbers or an unsolicited, pre-approved credit card complete with application.

• Your car. If someone broke in, what personal information would he or she find? Old bills and credit card receipts? Insurance card? What else?

• Your trash. It may be hard to believe, but "dumpster diving" is a gold mine for a determined thief who could find discarded credit cards, bills and bank statements.

• Your computer. Think about the personal information stored there, such as tax returns, account data, and e-mails.

• Yourself. Have you ever given out personal information over the phone to a stranger or on an unsecure Web site?

Although there's no ironclad protection from identity theft, this crime is most often one of convenience. If you make it difficult for someone to swipe your identity, the thief may look elsewhere for an easier target.

Rule 1: Be defensive with personal information
Give out personal information in person, over the phone or online only when you're certain you know with whom you're communicating or when you initiated the contact.

• Most importantly, guard your Social Security number. Keep it in a safe place (not your wallet!). Use it to identify yourself only when necessary. Don't have it printed on your checks.
• When online, only give the information required-often marked with an asterisk (*)-and no more.

Rule 2: Protect your credit and your bottom line

• Carefully check your financial statements every month for suspicious activity. If you spot something, immediately alert your credit card company or the creditor.
• After any cash machine, credit card or debit card transaction, take the receipts with you.
• Tear up or shred credit card or bank statements, solicitations and other records that contain personal financial information when you no longer need them.

Rule 3: Create strong passwords and keep them secret
Your first line of defense in the virtual world begins with your password or your personal identification number (PIN).

• Keep your passwords and PINs a secret. Keep them to yourself, and remember them without writing them down.

• Create strong passwords that you can remember. Passwords should have at least eight characters; include a combination of letters, numbers and symbols; and be easy for you to remember but difficult for others to guess.

• Manage your passwords. To balance safety and practicality, create a handful of strong passwords to protect the sites you want to keep most secure, such as your bank's Web site or your computer. Then create another small set of easier-to-remember passwords you use everywhere else.

• Protect your laptop with a password. This provides added security while you're in the office and on the road.