"Consumers are unaware of the rights they have," said Karen Gross, a professor at New York Law School. So knowing your legal rights is the first step to halting abusive debt-collection tactics.

Here are a few tips from regulators, plaintiff attorneys and consumer advocates:

* Debt collectors may not contact you at inconvenient times -- such as before 8 a.m. or after 9 p.m. -- or places, such as work, unless you agree.

* Debt collectors may not use obscene language, threaten violence or harm, or falsely imply that you have committed a crime and/or will be arrested if you don't pay your debt. They may not falsely represent themselves as attorneys or working in an attorney's office and may not threaten legal action unless it is actually intended (and often, it is not).

* Collectors are not supposed to contact anyone other than the debtor more than once, and then only to find out how to reach you. They may not tell anyone else that you owe money.

* Once they contact you by phone, they must follow up, sending you a written notice within five days, telling you the amount of money you owe and the creditor. If you don't owe the money, you have 30 days to write a letter to the collector. Once a collector receives your letter, the company is not supposed to contact you again, except to send proof of debt (such as a copy of the bill) or to notify you of a specific action, such as pursuing the claim in court or arbitration.

* If a creditor or collector sends you a legal notice, do not ignore it. The National Consumer Law Center says most collection suits and arbitration proceedings against consumers result in default judgments because consumers fail to respond to the legal notices. When they fail to respond, collectors may proceed to request a payment order from the court, and in many states may seek to garnish wages, even if the debt is not valid. On the other hand, the law center says cases are often dismissed when a consumer challenges the validity of the claim.

* If the claim is valid, be careful about the information you provide, especially personal account numbers.

* Know what the statute of limitations is in your state. If the debt is older than the legal time period, collectors cannot sue you for the money. Dale W. Pittman, a Virginia lawyer, also cautions consumers to carefully consider whether they want to repay even a portion of an old debt. Paying even a small amount, he said, could revive the debt under the statute of limitations and prompt more collection calls. It could also have an adverse affect on your credit rating by reflecting recent activity on a bad debt.

* For more information, or to file a complaint, call the Federal Trade Commission at 877-382-4357 or visit the agency's Web site: www.ftc.gov.

-- Caroline E. Mayer