The problem: Both Blue Cross and H&R Block have made the mistake of sending out mass mailings with customers' Social Security numbers printed right on the mailing labels. Inside your office, if your mail room and mailboxes aren't secure, neither are the sensitive documents that flow through them.

The solution: Never use Social Security numbers as customer ID codes. Mail-room employees should be screened with the same diligence applied to IT hires, and mail rooms should be secured with locks. Consider replacing employee mail slots with lockable boxes from a company like Postal Products Unlimited.