Chess Opening Theory/1. d4/1...Nf6/2. Bf4/2...d5/3. e3

London System Main Line with ...d5

London System - Main Base Position
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/ppp1pppp/5n2/3p4/3P1B2/4P3/PPP2PPP/RN1QKBNR b
Moves: 1. d4 Nf6 2. Bf4 d5 3. e3

The London System is a solid and flexible opening system for white that can be played against various setups by black. After the moves:

1. 1. d4 d5 2. Bf4 Nf6 3. e3 or
2. 1. d4 Nf6 2. Bf4 d5 3. e3

The main ideas for both sides in the London System's main line are:

For White:

1. Development and Structure: Nf3, Be2, c3, and often Nbd2 followed by a potential e4 break or the more restrained h3 and O-O. The pawn on d4 and the pawn on e3 provide a solid central structure.
2. Queenside Expansion: With moves like a4-a5 or a queenside pawn storm with b4, aiming for a potential minority attack.
3. King Safety: Usually achieved with O-O. The rook on f1 might later swing over to the c-file or e-file.
4. Central Break: Depending on Black's setup, White can aim for e4 at some point.

For Black:

1. Challenge the Bishop: ...c5 or ...Nh5 can be played to challenge White's strong Bf4.
2. Development: e6 followed by Be7, O-O, and Nbd7 or Nc6. Depending on the situation, the light-squared bishop can be developed to d7, f5, or g4.
3. Central Control: Black usually maintains a pawn on d5 and can consider playing ...e5 under the right conditions.
4. Queenside Counterplay: Black can look for counterplay with moves like ...a6 and ...b5, depending on White's play.

For a general introduction to the London System, take a closer look at 1. d4 d5 2. Bf4

Theory table

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

1. d4 d5 2. Bf4 Nf6 3. e3

	3
System with e6	... e6	=
Early c5	... c5	=

.

References

Bibliography

• Win with the London System. 2005. Sverre Johnsen, Vlatko Kovačević. ISBN 1-9046-0035-2.
• Chess Opening Crash Course: The London System