Chess Opening Theory/1. c4

English Opening
a b c d e f g h 8 8 7 7 6 6 5 5 4 4 3 3 2 2 1 1 a b c d e f g h
Position in Forsyth-Edwards Notation(FEN) rnbqkbnr/pppppppp/8/8/2P5/8/PP1PPPPP/RNBQKBNR
Moves: 1.c4
ECO code: A10-A39

English Opening

1. c4

This opening is very flexible. It can transpose into many others:

1...e5 is a "reversed" Sicilian Defence.

1...c6 will usually either transpose into the Caro-Kann Defence or the Slav Defence.

1...e6 will probably end up in a Queen's Gambit Declined.

1...Nf6 or 1...g6 are likely to transpose into an Indian Defence.

1...d5 is seldom played but may transpose into the Queen's Gambit.

1...f5, the Anglo-Dutch Defence, leads to sharp tactical lines for black, but can open a powerful kingside attack.

1...b5 normally gives good chances for black, even though the Halibut Gambit is considered unsound at the professional level.

Most "pure" English lines come from the Symmetrical Variation (1...c5) and are quite hard to play and to understand.

Statistics

Approximately chances: White win 37%, Draw 34%, Black win 29%
Estimated next move popularity: Nf6 31%, e5 23%, e6 13%, c5 12%, g6 8%, c6 6%, f5 4% other moves less than 2%

Theory table

For explanation of theory tables see theory table and for notation see algebraic notation

1.c4
	1	2	3	4	5
	c4 Nf6	Nc3 e6	e4 c5	e5 Ng8	Nf3 Nc6	∞
	... e5	Nc3 Nc6	Nf3 Nf6	g3 d5	cxd5 Nxd5	∞
Symmetrical Variation	... c5	Nf3 Nf6	g3 b6	Bg2 Bb7	O-O g6	=
	... c6	Nf3 d5	g3 Nf6	Bg2 dxc4	O-O Nbd7	∞
	... g6	e4 e5	d4 Nf6	dxe5 Nxe4	Bd3 Nc5	∞
	... e6	Nc3 Bb4	Qb3 Nc6	Nf3 Nf6	a3 Bxc3	∞
	... f5	Nf3 Nf6	g3 g6	Bg2 Bg7	O-O O-O	∞
	... d5	cxd5 Qxd5	Nc3 Qa5			+=
	... b5	cxb5 a6	bxa6 Bxa6			+=
Myers Defence	... g5	d4 Bg7	Nc3 h6	e4		+=

When contributing to this Wikibook, please follow the Conventions for organization.

References

• Modern Chess Openings: MCO-14. 1999. Nick de Firmian, Walter Korn. ISBN 0-8129-3084-3.

• Batsford Chess Openings 2 (1989, 1994). Garry Kasparov, Raymond Keene. ISBN 0-8050-3409-9.