Domain is a simple game played on a 9×9 square grid. Players take turn placing coloured plastic pieces onto the board. The pieces have different areas and shapes. The aim of the game is to have the largest area at the end of the game.

When pieces are placed, they may cause adjacent pieces on the board to flip over, depending on the variant played. In one variant, only the opponent’s pieces are turned over. In another, all adjacent pieces are turned over. In yet another variant, the pieces are divided up equally before starting, instead of players drawing from a standard pool.

Game consists of rules, a 9×9 board and 26 plastic pieces, coloured on both sides.