Good Bishop vs Bad Bishop
A "bad bishop" is blocked by its own pawns, stuck behind a wall of fixed pawns on its own colour, with limited mobility. A "good bishop" moves freely on open diagonals, unobstructed by its own pawns. The good/bad bishop distinction is one of the most important positional evaluations in chess.
What makes a bishop "bad"
A bishop is "bad" when:
- Your pawns are fixed on the same colour as the bishop.
- The bishop cannot influence the key areas of the position.
- The bishop's diagonals are blocked. A bishop on e2 behind pawns on d3, e4, and f3 is thoroughly bad, it's a tall pawn. Conversely, a fianchettoed bishop on g2 raking down the long diagonal is a "good" bishop.
Exploiting a bad bishop
- Exchange the opponent's good bishop. Leave them with only the bad one.
- Fix pawns on the bishop's colour. Force the opponent's pawns onto the same colour as their bishop.
- Create outposts on the opposite colour.
- Head for the endgame. A bad bishop is especially painful in endgames where the king can attack squares the bishop can't defend.
Improving your bad bishop
- Trade it. Exchange the bad bishop for a useful opponent piece.
- Reposition it. Manoeuvre it outside the pawn chain (e.g., Bc1-d2-e3-c5 in many QGD positions).
- Change the pawn structure. Push the pawns that are blocking it, if you can play d3-d4 and open the diagonal, the bishop improves dramatically.
- Place it outside the pawn chain. A bishop in front of its own pawns is almost always better than one behind them.
Related concepts
Understanding the good/bad bishop distinction directly connects to colour complex strategy, knight vs bishop evaluations, and bishop pair advantages. Study the interplay between all these concepts for a complete understanding of minor piece play.