What can I do about telephone slamming?

 Deregulation of the telephone industry has increased the number of telephone service providers who are competing to get your long distance and local toll telephone service. While most companies follow federal and state rules when obtaining your consent and changing your telephone service, others do not. Instead, these companies engage in a practice commonly known as 'slamming.'

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PSC Consumer Guide: Slamming
What is Slamming? How do I know I have been slammed?
URL: http://www.dps.ny.gov/slamming.htm