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• The most recent discard can be claimed by any of the other players, provided they can complete a winning hand, a pung or a kong. A claimed pung or kong may result in players losing their turn, as play continues from the claiming player, not from the discarding player.
• The player about to begin his turn can claim the most recent discard for a chow. If the player doesn’t want to claim the discard, he begins his turn by picking the next tile from the wall.

When claiming a tile for a chow, pung or kong, the player first clearly calls “chii”, “pon” or “kan” respectively. Secondly, the player reveals the matching tiles from his hand. And thirdly, he discards a tile from his hand and takes the tile called for. For the third step the order of the two actions is not important: the player can take the claimed tile first and then discard, or the other way round.
Errors in the order above when claiming tiles should be pointed out to the player, but not penalized.
The player should take the claimed tile before the next two players have made a discard. Failing to take the claimed tile in a timely manner results in a dead hand, since the player will have a false group.

Swap-calling (kuikae) is not allowed. It is forbidden to:
- Call a tile and immediately discard the same tile.
(E.g.: calling , melding , and discarding .)
- Call a tile for a chow and immediately discard the tile from the other side of the chow.
(E.g.: calling , melding , and discarding .)

The last discarded tile can be claimed for a chow, pung or kong until the next player draws. But it can be claimed for a win until the next player discards.

Claiming a tile to win takes precedence over any other claim. When several players declare a win on the same discarded tile, the player closer to the discarder, according to the turn order, takes precedence.
If no one declares a win, the first call for a chow, pung or kong takes precedence. If the calls are simultaneous, or if it's not clear which one was first, then claims for a pung or kong take precedence over claims for a chow.

Players are not limited in time to play, but they are expected to play at a reasonable pace. A player drawing too fast for the other players to have time to call, or repeatedly taking an overlong time, can be penalized for obstruction at the referee discretion.

If a player draws too fast for the other players to have time to call, the call is still valid and the drawn tile must be put back into the wall.

By courtesy, East player is expected to wait until each player has sorted his hand before making his first discard.

A tile can only be claimed for a chow by the player to the right of the discarder. Claiming the last discarded tile for a chow is done by clearly saying “chii” and placing the tile face-up along with the two tiles from the hand that complete the group.

A player can make a chow with only self-drawn tiles. He does not declare it.

Claiming the last discarded tile for a pung is done by clearly saying “pon” and placing the tile face-up along with the two matching tiles from the hand.

A player can make a pung with only self-drawn tiles. He does not declare it.

Claiming the last discarded tile for a melded kong is done by clearly saying “kan” and placing the tile face-up along with the three matching tiles from the hand. After revealing a new kan dora, the player takes a replacement tile from the dead wall and continues his turn as if he had drawn a tile from the wall. The dead wall always comprises 14 tiles, so after a kong is made the dead wall is replenished with the last tile of the live wall.

A melded pung may be extended to a melded kong in a player’s turn after the player has taken a tile from the wall (as a normal draw or as a replacement tile), i.e. not in a turn where a tile was claimed for making a chow or pung. The player must say “kan” clearly, place the fourth tile by the rotated tile of the pung, allow a reasonable time for other players' winning declarations, and then reveal a kan dora indicator and take a replacement tile. The dead wall is replenished with the last tile of the live wall.

A concealed kong may be declared in a player’s turn after the player has taken a tile from the wall (as a normal draw or as a replacement tile), i.e. not in a turn where a tile was claimed for a chow or a pung. The player must say “kan” clearly, reveal the four tiles of the kong, then turn the two outside tiles face-down, reveal a kan dora and then take a replacement tile. The dead wall is replenished with the last tile of the live wall.
It's allowed to turn the two middle tiles face-down instead of the two outside tiles.
A player still has a concealed hand after declaring a concealed kong, if the player has no open groups.
A concealed kong cannot be robbed, except to win on the Thirteen Orphans yaku.

Note that four identical tiles only make a kong if they are declared as being a kong.

Only four kongs can be declared per hand. When the fourth kong is made the game continues, but no further kong may be declared. Under no circumstance can a fifth kong be made.

Tiles in melded groups, as well as concealed kongs, cannot be rearranged to form other groups, and they cannot be discarded.
After calling a tile, the relevant tiles from the hand are immediately exposed. It is allowed to make the discard before the claimed tile is taken. If the claimed tile is not taken within the next two opponents’ turns, i.e. before another two discards has been made, the player has a dead hand.
Melded groups and concealed kongs are placed to the right of the player's tiles in clear view for all players. Claimed tiles are rotated to indicate which player made the discard.
• If the tile was discarded by the player sitting on the left, the claimed tile is put on the left side of the group.
• If the tile was discarded by the player sitting in front, the claimed tile is put in the middle of the group.
• If the tile was discarded by the player sitting on the right, the claimed tile is put on the right side of the group.
A big melded kong (melded kong made by calling on a concealed pung) has one rotated tile.
A small melded kong (melded kong made by promoting a melded pung) has two rotated tiles: the extending tile is placed by the previously rotated tile.
A concealed kong hasn't rotated tiles; instead the two outside (or central) tiles are turned face-down.