Colle System

Colle System
abcdefgh
8
d4 white pawn
c3 white pawn
d3 white bishop
e3 white pawn
f3 white knight
a2 white pawn
b2 white pawn
f2 white pawn
g2 white pawn
h2 white pawn
a1 white rook
b1 white knight
c1 white bishop
d1 white queen
e1 white king
h1 white rook
8
77
66
55
44
33
22
11
abcdefgh
Basic Colle System structure for White. Common continuations include Nbd2 and 0-0.
Movesfor White: d4, Nf3, e3, Bd3, c3
ECOD05
Named afterEdgard Colle
ParentQueen's Pawn Game,
Closed Game,
Zukertort Opening,
or Indian Defence
Synonym(s)Colle–Koltanowski System

The Colle System, also known as the Colle–Koltanowski System, is a chess opening system for White, popularised in the 1920s by the Belgian master Edgard Colle and further developed by George Koltanowski.

The Colle is characterised by several moves. White's center pawns are developed to d4 and e3, the king's knight is developed to f3, the king's bishop is developed to d3, and the queen bishop's pawn (c-pawn) is developed to c3. Common continuations include development of the queen's knight to d2 (Nbd2) and kingside castling (0-0). A major theme of the Colle System is the ambition to play a well-timed e4, where the square is defended by the bishop on d3, the knight on d2 (following Nbd2), and possibly the rook on e1 (following 0-0 and Re1). Although sometimes described as a specific sequence of moves, the Colle System is not a fixed line of play, but rather a system for White where the moves may be permuted at the player's discretion. When a game opens with most or all of the above moves, to the exclusion of moves which typify other openings, the game may be described as "a Colle System".

Although criticised by some and used infrequently in master play, the Colle is regarded by others as a solid and playable opening.