If your debt goes to collection, for the most part the debt collector can employ all of the collection methods available to the original creditor. But some bill collectors and collection agencies can be quite aggressive. It's important to know what debt collectors and collection agencies can and cannot do, and what to do if a bill collector violates the law. If the original creditor sold your debt to a debt buyer, you might encounter different issues. Learn about debt buyers, some of the abusive tactics they use, and how to protect yourself.