Casinos combat card counting through a variety of methods aimed at reducing its effectiveness. They often shuffle cards more frequently or use continuous shuffling machines, making it harder to track the deck. Many casinos also employ multiple decks, which complicates card counting even further. Surveillance teams monitor players closely for suspicious behavior, and if card counting is suspected, they may impose betting limits or ask the player to leave. Some casinos alter game rules or introduce new variations to make card counting less profitable. Finally, players caught counting cards may be banned from the casino altogether, as casinos have the right to refuse service to anyone they suspect is gaining an unfair advantage.