Shogi opening

A shogi opening (戦法 senpō) is the sequence of initial moves of a shogi game before the middle game. The more general term for the beginning of the game is 序盤 joban.

A joseki (定跡 jōseki) is the especially recommended sequence of moves for a given opening that has been considered balanced play for both sides by professional players. Josekis also typically include commentary about the possible reasons to deviations from the joseki especially regarding blunders.

There are many of different openings with many named variants.

Shogi openings are generally slower than that of chess, due to the larger board and less mobile pieces. But since a quick offense will leave a player's home territory open to drop attacks as soon as pieces are exchanged, one aim of the opening is to build up defenses for the king

There are two usual first moves. A player can move the rook pawn forward (P-2f), or, more commonly, advance the pawn above and to the right of the bishop (P-7f). The former is known as a rook opening and the latter a bishop opening.

With a bishop opening, it's common to exchange bishops by having one capture the other. This allows each player to put their newly captured bishop into play anywhere on the board on their next move although care must be taken to avoid weaknesses in defense which may allow for a bishop drop from their opponent. However, it is not advantageous to exchange bishops if your opponent has a better defensive setup, or more lines of attack. Moreover, making a bishop exchange constitutes one turn loss, so it's not advised without a good reason.

Many common opening attacks involve advancing a silver and ideally pawns, protected by other pieces. Because silvers have more possibilities for retreat, silvers are generally considered superior as attacking pieces in the opening and middle game while golds better defend their sides and are superior as defensive pieces. It is common practice to defend the king with three generals, two golds and a silver.

Because defense is so important, and because shogi pieces are relatively slow movers, the opening game tends to be much longer in shogi than in international chess, commonly with a dozen or more moves to shore up defenses before the initial attack is made. As part of the defense, typically the king is moved to the side in a castle with three generals. Leaving a king on its original square (居玉 igyoku or "sitting king") is a particularly dangerous position.

Over many decades, Japanese professional players have invented various jōseki (定跡), which determine moves and sequences which are thought to be the best for a particular situation. It also covers a branch of different variations within an intricate strategy, including alternative options and the certain consequences that some moves may bring.

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