In Go-Fish, a single deck of cards is used. The cards are mixed thoroughly, and then dealt alternately until each player has a hand of five cards. The rest of the deck is placed face-down on the table. If any player has a pair of cards with the same face value, the player immediately lays down the pair into her “pot.” She never holds a pair in her hand.
Players then take turns being the “active” player. The active player chooses one of the cards in her hand and asks the opponent, for example, “Do you have any threes?” If the opponent has a 3 he surrenders it to the active player, and the active player puts the pair into her pot. If the opponent has no 3 then he says, “Go fish,” and the active player draws a card from the top of the deck. If the active player draws a 3 she says, “Fished my wish,” and puts her pair into the pot. If she draws a card that matches a different card in her hand then she puts her pair into the pot without declaring “Fished my wish.” The active player remains active until she is asked to “go fish” and fails to fish her wish. Her turn ends and the opponent becomes the active player.
Sometimes the active player is left with no cards in her hand. When this happens, she draws a single card from the top of the deck and continues by asking her opponent for that card. Note that a passive player may be left with no cards in his hand, too. In this case, he does not draw a card from the deck. He simply will say, “Go fish,” to any request. (The active player must make a specific request, even though she knows the response beforehand, because otherwise there would be no way to determine whether she fished her wish.)
The game ends when there are no more cards to draw from the deck and all cards have been placed into the pots. There are never any cards left in the hands because there are an even number of cards of each face value in a deck (four), and so they are all paired off in the end. Players then count the number of cards in their pots. The player with the most cards in his or her pot is declared the winner.