Thematic tournament

In a thematic tournament, the organizer fixes the chess starting point in advance. The event may require a particular opening, meaning a sequence from the early phase of a game, a specified line of moves, or a set position. Players cannot choose alternatives during the compulsory portion; their independent decisions begin after the prescribed sequence ends.

The format lets many games investigate the same problem from different directions. Two players can develop entirely different plans even though they received the same starting position. When each pairing includes more than one game, the event rules may reverse colors so that both players examine the theme from each side.

The format is especially suited to correspondence chess, where moves are transmitted over distance and players have substantial analysis time. The rules of the International Correspondence Chess Federation, abbreviated ICCF, treat compulsory opening moves as part of the time-control calculation and adjust the available reflection time during the first control period.