Hollywood studios are planning to sue internet users caught swapping pirated movies.
Following music industry measures to clamp down on illegal song piracy, the Motion Picture Association of America (MPAA) are launching civil suits seeking damages of up to $30,000 (€23,200) per film.
The MPAA want to issue the first lawsuits, before high-speed internet access becomes more widespread.
MPAA head Dan Glickman says: "This was not an easy decision, but it must be done now before illegal online file-sharing of movies spins out of control. Illegal movie trafficking represents the greatest threat to the economic basis of movie-making in its 110-year history.
"People who have been stealing our movies believe they are anonymous on the internet, and wouldn't be held responsible for their actions. They are wrong. We know who they are, and we will go after them, as these suits will prove."
According to MPAA figures, movie studios lose $3bn (€2.3bn) each year because of internet piracy.