Recommended level: players familiar with algebraic notation and fundamental development principles.

Core idea: play an adaptable London — solid in structure, but active in its pawn breaks and piece plans.

Table of Contents

• 1. General Idea
• 2. The Typical Position
• 3. Overview of Black's Responses
• Part I — The King's Fianchetto
• Part II — Nimzo-Indian and QGD Structures
• Part III — Queen's Indian Structures
• Part IV — Slav Structures
• Part V — Other Lines after 1.d4 d5 2.Nf3
• Part VI — The Dutch Defense
• Recurring Patterns
• Revision Sheet

Goal. This guide presents a complete repertoire against the main responses to 1.d4 and 2.Nf3. Variations and plans are presented in a practical manner, with special attention to critical positions, pawn breaks, and typical manoeuvres.

1. General Idea

The London System is presented as a solid and versatile setup for White. Its classical form relies on d4, Nf3, Bf4 and e3, but the repertoire studied here adapts the move order to the structure Black chooses.

The goal is not to claim an automatic theoretical advantage. Rather, the repertoire aims for playable positions — often objectively equal but slightly easier to handle for White. Black can rarely simplify completely or repeat moves, which generally keeps the game combative.

Guiding Principles

• Develop the dark-squared bishop before e3 whenever possible.
• Don't play mechanically: the system becomes dynamic with c4, Nc3, e4, h4, or queenside expansion.
• Meet unambitious Black play by seizing space in the centre or on the queenside.
• Use h3 to prevent ...Bg4 or ...Nh5 and provide a retreat square for the bishop.
• Open the centre when White has developed more pieces.
• In attacking positions, centralise your pieces and exchange your opponent's active pieces.

2. The Typical Position

The most representative starting position of the repertoire is:

Basic sequence: 1.d4 Nf6 2.Nf3 e6 3.Bf4, usually followed by e3, c3 or c4 depending on Black's response.

The bishop on f4 exerts pressure on c7 and controls the b8-h2 diagonal. But it must not remain on this diagonal at all costs: Bg3, Bh2, Bg5 or Be3 are all planned retreats and transformations in this repertoire.

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3. Overview of Black's Responses

The system is organised into six major families:

1. King's Fianchetto: ...Nf6, ...g6.
2. Nimzo-Indian / Queen's Gambit Declined structures: ...Nf6, ...e6, followed by ...d5.
3. Queen's Indian structures: ...Nf6, ...e6, followed by ...b6.
4. Slav structures: ...Nf6, ...d5, or ...d5 before ...Nf6.
5. Other systems after 1.d4 d5 2.Nf3, notably ...e6, ...c6, ...Bf5.
6. Dutch Defense: 1.d4 f5.

Rare moves like early ...b6, ...d6 or ...g6 are not covered in depth. If Black does not contest e4, the recommended approach is to play e4 in a principled manner, possibly transposing to the Pirc, Philidor or Owen's Defense.

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Part I — The King's Fianchetto

4. The Dynamic Plan Against 1...Nf6 2...g6

The central recommendation is:

1.d4 Nf6 2.Nf3 g6 3.Nc3!

3.Nc3 threatens e4 and seeks to dominate the centre. If Black plays 3...Bg7, White plays 4.e4 immediately.

Model Line Against ...Bg7 ...d6

1.d4 Nf6 2.Nf3 g6 3.Nc3 Bg7 4.e4 d6
5.Be2 O-O 6.O-O Nc6 7.d5 Nb8 8.Be3

Key idea — space and manoeuvre. White has more space and better queenside development. The indicated plan is a4, then Nf3-d2-c4. If Black plays ...f5, White generally keeps the centre closed with f3.

5. Against ...c5

1.d4 Nf6 2.Nf3 g6 3.Nc3 c5 4.d5 Bg7 5.e4 d6 6.Bb5+

White's plan. The point of Bb5+ is to disrupt Black's coordination. After 6...Bd7 7.a4 Bxb5 8.axb5 O-O 9.O-O Nbd7 10.Qe2, White has a slight edge and a clear plan: Rd1, h3, Bf4, then e5.

The push a4 is recurring: it answers ...a6 and prevents Black's expansion with ...b5.

6. Against ...d5

After:

1.d4 Nf6 2.Nf3 g6 3.Nc3 d5 4.Bf4

the plan often consists of c6, h3, e3, Be2, castling and expansion via a4-a5.

A representative line is:

4...c6 5.h3 Bg7 6.e3 O-O 7.Be2 Nbd7
8.O-O Re8 9.Bh2 a5 10.a4 b6 11.Re1 Bb7 12.Bd3

White wants to play e4. After 12...c5 13.Nb5 Rc8 14.b3, all White's pieces are well placed; the plan is Rc1 and c4.

Another tactical idea appears with 4...Bg7 5.Nb5!. The knight targets c7; ...Na6 is practically forced to defend that square, then White can play e3 and return to c3. After ...c6, Bxa6 can damage Black's structure:

1.d4 Nf6 2.Nf3 g6 3.Nc3 d5 4.Bf4 Bg7
5.Nb5 Na6 6.e3 c6 7.Nc3 O-O 8.Bxa6 bxa6 9.Ne5

This sequence leaves White with a compromised Black pawn structure and pressure on the c6 pawn.

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Part II — Nimzo-Indian and QGD Structures

7. The Basic Scheme

Against 1...Nf6 2...e6, White plays:

1.d4 Nf6 2.Nf3 e6 3.Bf4

When Black plays ...d5, the recommended plan is often c3, e3, then Nbd2 or Nc3. The strategic idea is to keep slightly more active pieces, especially the White bishop facing Black's c8 bishop.

8. The Active Move Against ...c5 and ...Qb6

1.d4 Nf6 2.Nf3 e6 3.Bf4 c5 4.c3 Qb6 5.Qb3

White offers a queen trade to improve their structure. The critical line given is:

5...cxd4 6.Qxb6 axb6 7.Nxd4 d5 8.Nb5 Na6
9.f3 Bd7 10.N1a3 Bc5 11.O-O-O O-O 12.Kb1 Bc6 13.g4

White has a clear attacking plan on the kingside. Black's knight on a6 has a less promising future.

9. Against ...d5 ...Bd6

1.d4 Nf6 2.Nf3 e6 3.Bf4 d5 4.c3 Bd6
5.e3 Bxf4 6.exf4 O-O 7.Nbd2 c5 8.dxc5 Qc7 9.g3

It is better to keep the f4 pawn — important for controlling e5 — rather than defending the c5 pawn at all costs. After ...Nbd7, Nb3, ...a5, Bg2, ...a4, Nbd4, White castles and continues with Re1, Qc2, Rad1, keeping the f5 push in mind.

10. The Ambitious Line with ...Nc6 and ...Bd6

1.d4 Nf6 2.Nf3 e6 3.Bf4 d5 4.c3 c5 5.e3 Nc6
6.Nbd2 Bd6 7.Bg3 O-O 8.Bd3 b6 9.e4!

The e4 push tests Black's structure:

9...dxe4 10.Nxe4 Nxe4 11.Bxe4 Bb7 12.Qa4 Rc8
13.Rd1 Qe7 14.dxc5 Bxc5 15.O-O

White has strong central activity and threatens among others b4 to win Black's bishop.

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Part III — Queen's Indian Structures

11. Black's Fianchetto with ...b6

The typical sequence is:

1.d4 Nf6 2.Nf3 e6 3.Bf4 b6 4.e3

Black aims for ...Bb7, ...c5 and sometimes ...e5. White develops the king's bishop to d3, plays h3 if necessary, and prepares e4.

12. The Response Against ...c5

5.Nc3! is a concrete response, with the threats d5 and Nb5:

1.d4 Nf6 2.Nf3 e6 3.Bf4 b6 4.e3 c5 5.Nc3

Black cannot always prevent both threats. Example:

5...a6 6.d5 Bb7 7.e4 b5 8.Qe2 Qa5 9.Nd2 Be7
10.g3 exd5 11.e5 Ne4 12.Ndxe4 dxe4 13.Bg2

The centre gives White space and O-O, Nxe4 then Qg4 constitute attacking ideas.

Another line shows the tactical motif:

5...cxd4 6.Nxd4 a6 7.Qf3 d5 8.Bxb8 Rxb8
9.Nc6 Qc7 10.Nxb8 Qxb8 11.Bd3

Qf3 provokes ...d5, after which Nc6 forks queen and rook. White wins material.

13. Against ...Bb7 and Knight Retreat

1.d4 Nf6 2.Nf3 e6 3.Bf4 b6 4.e3 c5 5.Nc3 Bb7
6.Nb5

The responses ...Nd5 and ...Na6 are analysed. After ...Nd5 7.Nd6+ Bxd6 8.Bxd6, White has the bishop pair and Black's king cannot easily castle. After ...Na6, White's plan is Nd2, g4 and g5, pressuring the passive knight on a6 and bishop on b7.

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Part IV — Slav Structures

14. Why the Repertoire Prefers 3.c3

After:

1.d4 Nf6 2.Nf3 d5 3.c3

the move c3 waits to see Black's structure before developing the bishop. It also prepares Qb3 against a Black bishop developed to f5, and constitutes a specific response to ...c5.

To remember. These positions may look more like a Slav or QGD than a classical London. The goal remains a playable, well-prepared position.

15. Against ...c6 and Bishop Development

The main recommended line begins with:

1.d4 Nf6 2.Nf3 d5 3.c3 c6 4.Qc2

Against ...Bg4

The attacking motif is:

4...Bg4 5.Ne5 Bh5 6.Qf5 Nbd7 7.Qh3

The queen threatens g4. If Black tries to exchange it with ...Qc8, White plays Qh4, renewing the threat. An illustrative line is:

7...Qc8 8.Qh4 Nxe5 9.dxe5 Qg4 10.Qxg4 Nxg4
11.h3 Nh6 12.c4 e6 13.cxd5 exd5 14.g4 Bg6 15.f4

The Black knight can become misplaced; ...Nxe5? loses a piece after f4 and g4.

Against ...g6 and ...Bf5

1.d4 Nf6 2.Nf3 d5 3.c3 c6 4.Qc2 g6 5.h3 Bg7
6.Bf4 O-O 7.e3 Bf5 8.Qb3 Qb6 9.Nbd2 Nbd7 10.g4

h3 prepares g4. After ...Be4 11.g5 Nh5 12.Bh2, White aims for the bishop pair; Black's knight on h5 is out of play.

Against ...Qc7

1.d4 Nf6 2.Nf3 d5 3.c3 c6 4.Qc2 Qc7 5.c4

White poses a dilemma: capture on c4 and let White seize the centre, or play ...e6 with a passive c8 bishop. The recommended continuation is:

5...dxc4 6.Qxc4 Bf5 7.g3 e6 8.Bg2 Nbd7
9.O-O Be7 10.Nc3 O-O 11.Nh4

White has space and can aim for e4, Qb3 and Bf4.

16. The Critical Case 3...c5

3...c5 is the critical response to 3.c3:

1.d4 Nf6 2.Nf3 d5 3.c3 c5 4.dxc5 e6 5.b4

White accepts the temporary sacrifice and tries to keep the pawn while developing the queenside:

5...a5 6.e3 axb4 7.cxb4 b6 8.Bb5+ Bd7
9.Bxd7+ Nbxd7 10.a4 bxc5 11.b5

Key position. This position is atypical: White has two connected passed pawns on the queenside, Black a protected passed pawn in the centre. White has a plan that is easier to formulate, though the position is not claimed to be winning.

The model continuation shows the necessary precision:

11...Bd6 12.Bb2 O-O 13.O-O Qc7 14.Nbd2 e5 15.e4 c4
16.Qc2 Rfc8 17.Rfc1 Bb4 18.Bc3 Bxc3 19.Qxc3 dxe4 20.Ng5

White must prevent ...c3 and maintain piece activity.

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Part V — Other Lines after 1.d4 d5 2.Nf3

17. Against 2...e6

It is preferable to play Bf4 before e3. If Black plays ...Bd6 Bxf4, White generally recaptures with the e-pawn:

1.d4 d5 2.Nf3 e6 3.Bf4 Bd6 4.e3 Bxf4 5.exf4

When Black's knight goes to e7, White can launch a kingside attack:

5...Ne7 6.h4 b6 7.h5 h6 8.g4 c5 9.Nc3

Black castling kingside becomes dangerous; White prepares f5 or g5 and can castle long.

If Black castles quickly:

1.d4 d5 2.Nf3 e6 3.Bf4 Bd6 4.e3 Ne7 5.Bg3 O-O
6.c4 b6 7.Nc3 Bb7 8.Rc1 Nd7 9.cxd5 Nxd5
10.Nxd5 Bxd5 11.Bb5

White has active pieces and can target the c7 pawn via Qa4 or Bc6.

Against ...c5, a recommended approach sometimes consists of capturing on c5 then playing c4 to open the centre:

1.d4 d5 2.Nf3 e6 3.Bf4 Bd6 4.e3 Ne7 5.Bg3 c5
6.dxc5 Bxc5 7.c4 Nbc6 8.Nc3 O-O 9.a3

18. Against 2...c6 and ...Qb6

1.d4 d5 2.Nf3 c6 3.Bf4 Qb6 4.Qc1 Nf6 5.e3 Bf5
6.c4 Nbd7 7.Nc3 e6 8.h3

After ...dxc4, Nd2 allows recapture with tempo against the queen:

8...dxc4 9.Nd2 Nd5 10.Nxc4 Qd8 11.Nd6+ Bxd6
12.Bxd6

White has a clear advantage thanks to the bishop pair and space.

If Black does not capture on c4:

8...Be7 9.c5 Qd8 10.b4 O-O 11.Be2

White has attacking chances on the queenside and prepares b5.

19. Against 2...Bf5

Early Black bishop development is punished by seizing space:

1.d4 d5 2.Nf3 Bf5 3.c4 e6 4.Nc3 c6 5.Qb3

Qb3 attacks b7, now vulnerable since the bishop left c8. After:

5...Qb6 6.c5 Qxb3 7.axb3 Nd7 8.b4 a6
9.Bf4 Rc8 10.Nd2

White's knight targets a5 and defending the b7 pawn becomes difficult for Black.

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Part VI — The Dutch Defense

20. Recommended Move Order

After:

1.d4 f5 2.Nf3

It is preferable to develop the knight before the London bishop. The continuation depends on Black's choice.

21. Against ...Nf6 ...e6

1.d4 f5 2.Nf3 Nf6 3.Bf4 e6 4.e3

White avoids playing c4 too early, as that would allow a Black bishop to arrive on b4 without being kicked. After ...Be7, h3, the bishop goes to d3 to support e4:

4...Be7 5.h3 O-O 6.Bd3 b6 7.O-O Bb7 8.c4
Ne4 9.Nfd2 Nxd2 10.Qxd2 d6 11.Nc3 Nd7 12.Bh2 e5
13.Qc2 e4 14.Be2 Kh8 15.b4

The centre is closed and White begins the queenside attack with Rab1 and c5. Black has no clear plan; ...f4 risks dropping the e4 pawn.

22. Against the Dutch Fianchetto

After 1.d4 f5 2.Nf3 Nf6 3.Bf4 g6, White plays c4, then Nc3:

1.d4 f5 2.Nf3 Nf6 3.Bf4 g6 4.c4 Bg7 5.Nc3 O-O
6.e3 d6 7.Be2 Nc6 8.Bg3

Bg3 is necessary to prevent ...Ne4 and is a preventive measure against ...e5. The line continues:

8...Nh5 9.Bh4 h6 10.d5 Na5 11.Rc1 c5
12.Nd2 Nf6 13.a3 b6 14.O-O

White has a slight edge thanks to a flexible structure and space. The plan is f4, e4, then an attack in the centre and on the kingside.

23. Against 1...g6 Without ...Nf6

Seize the centre immediately:

1.d4 f5 2.Nf3 g6 3.c4 Bg7 4.Nc3 d6 5.e4

After ...fxe4 Nxe4, White enjoys a space advantage. The model position is:

1.d4 f5 2.Nf3 g6 3.c4 Bg7 4.Nc3 d6 5.e4 fxe4
6.Nxe4 Nf6 7.Bd3 Nc6 8.h3 O-O 9.O-O e5
10.dxe5 Nxe4 11.Bxe4 Nxe5 12.Nxe5 Bxe5 13.Bh6 Re8
14.Qd2

White considers Rae1, f4 and g4. Black's position is passive, with a weakened kingside.

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24. Recurring Patterns to Remember

Bishop Development

The London bishop is an active piece, but its ideal square depends on the position:

• Bf4: basic development and pressure on c7.
• Bg3: preserves the bishop and may provoke ...Nxg3 or ...Bxg3.
• Bh2: prophylactic retreat, particularly before a queenside expansion.
• Be3: harmonious development in fianchetto structures.
• Bg5: possible when Black plays early ...Nh5.

Pawn Breaks

• e4: the central break when Black does not prevent it.
• c4: gaining space and opening the centre, especially against slow structures.
• h3: prevents ...Bg4 and ...Nh5, while giving h2 to the bishop.
• a4: stops ...b5 and sometimes prepares a5.
• g4, h4: attacks when Black's king is vulnerable or a knight is misplaced.

Squares and Knights

The f3 knight can go to d2-c4. The c3 knight can target b5, d5, e4 or return to c3 after a temporary manoeuvre. The repertoire frequently exploits:

• Nb5 against c7 or to exploit an uncastled Black king;
• Nd6+ as a tactical outpost;
• Nc6 for a fork;
• Ng5 in attack against h7;
• Nbd2 to support e4 or control c4/e4.

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25. Practical Conclusion

The London System is not an identical sequence of moves against everything. It is a family of structures linked by a few priorities: develop the dark-squared bishop in time, prevent Black's critical plans, then play actively with e4, c4, a4 or a kingside attack.

The most important practical rule is therefore: keep the spirit of the London, but respond concretely to Black's structure. Against a fianchetto, Nc3 and e4 often seize the centre. Against ...d5, c3 can wait and prepare a Slav-like struggle. Against ...e6 ...b6, Nc3 and e4 exploit the time Black needs to develop. In the Dutch, the order Nf3, then Bf4, preserves this flexibility.

Positions are frequently objectively balanced, but they offer great playability and a rich variety of White plans. It is this combination — solid structure, natural development and dynamic breaks — that defines the London of this repertoire.

26. Revision Sheet

Move Orders

• Against 1...Nf6 2...g6: 3.Nc3, then e4 if Black plays ...Bg7.
• Against 1...Nf6 2...e6: develop the bishop with Bf4 before e3.
• Against 1...Nf6 2...d5: the repertoire often prefers 3.c3 over 3.Bf4.
• Against 1.d4 d5 2.Nf3: play Bf4 before e3 against ...e6, but c4 against unambitious play or ...Bf5.
• Against the Dutch: Nf3 before Bf4; c4 and Nc3 become possible after ...g6 or after castling.

Plans to Memorise

Black Structure	White's Response or Plan
...g6 and ...Bg7	Nc3, e4, central space, then d5 or a4 depending on the line
...c5 against fianchetto	d5, e4, Bb5+, a4
...e6 ...d5	Bf4, c3, e3, harmonious development
...e6 ...b6	Bf4, e3, Nc3, e4
...d5 ...c6	c3, Qc2, then g4 against ...Bg4 or ...Bf5
...d5 ...c5	dxc5, b4, queenside development
Dutch with ...e6	Bf4, e3, h3, castle, then c4
Dutch with ...g6	c4, Nc3, e3, Bg3, then f4 and e4

Control Questions

1. Can the London bishop be developed before e3 in this line?
2. Is Black threatening ...Bg4, ...Nh5, ...Ne4, ...b5 or ...e5?
3. Should I prevent a ...b5 expansion with a4?
4. Does the position call for e4, c4 or a pawn attack on the kingside?
5. Are my pieces developed enough to open the centre?
6. Can the knight reach d2-c4, b5, d6 or c6 with tempo?

Study method. First learn the critical positions and their plans, then review the short variations checking the motif that justifies them: space gain, piece attack, line opening or exploitation of a development delay.