To help account for the contents of your wallet, it is a good practice to photocopy all credit cards and other identification cards on a periodic basis. Copy both sides of each license, credit card, library card, video rental card, etc. If your wallet or purse is stolen, the account numbers and phone numbers will be available to facilitate the calls you make to report your cards stolen. Keep the photocopy in a safe place.
If your wallet or purse is lost or stolen, cancel your credit cards immediately, but remember that the key is having the toll free numbers and your card numbers handy so you know whom to call. Keep those where you can find them easily. File a police report in the jurisdiction where it was stolen. This will provide credit companies proof you were diligent, and is the first step toward an investigation.
Call the three national credit-reporting organizations and the Social Security Administration immediately to place a fraud alert on your name and Social Security number.