Basic Play
The game starts with a coin flip to decide who serves first. After that, the person last scored upon has a chance to serve: placing the ball through the serving hole to start play. Play continues until someone calls time out, the ball is knocked off the table, a dead ball occurs (when neither team can strike it with his men) or when someone scores a point by getting the ball through the opponent's goal. Only the men on the rods may be used to move the ball, and no one may interfere with either player's ability to maneuver his rods. No one may jostle, lift, or otherwise maneuver the foosball table to alter the movement of the ball.
Fouls
Besides basic fouls regarding sportsmanship and fair play (if you think it's cheating, it probably is), foosball contains several specific instances of fouls. You cannot turn a single foosball man more than 360 degrees at one time, nor can you pass the ball directly from the five-man bar to the forward three-man bar. The ball may not be held on any one bar for longer than 15 seconds (10 seconds if the five-man bar has possession). Each of these cases constitutes a technical foul, which means that play stops and possession of the ball is given to the other team's forward three-man rod. He may make one shot with it, after which the ball returns to the spot of the technical foul. If a player commits three technical fouls in the course of a single match, he forfeits the match.
Victory Conditions
According to the USTSA, victory conditions are tied to the time of each match. Best two-out-of-three matches must end after 35 minutes, while best three-of-five matches must end after one hour. The player with the most points at the end of that time wins. In the event of a tie, a 10-minute overtime will take place to determine the winner. If the game is still tied after that period, one ball shall be put in play; the first one to score wins. Variants on victory conditions include straight scoring: a number is named and the first person to score that number of goals wins. In some cases, play must continue after that point is scored until one player has two more points than his opponent.