Chess Openings → London System

London System: one plan for everything

The London System starts with 1.d4, but what sets it apart is move order: the bishop comes out to f4 before you play e3 — in the reverse order you'd shut it in behind your own pawns. That's what lets the same development plan work almost regardless of Black's reply.

In short: after 1.d4 you play the same plan every time — Bf4 before e3, then Nf3, Nbd2, Bd3, c3, and short castling. You don't need to learn a separate reply to every Black move, because it's a system, not a set of variations. You can practice the full repertoire — with responses to the three most common Black setups — in the opening trainer, free and without an account.

The move order that defines the system

After 1.d4 d5 2.Bf4 the bishop lands on an active square before you block its own path with the e3 pawn. Next: Nf3 controls the center, e3 supports d4 and opens the way for the f1 bishop, and c3 defends d4 as well. The same pattern — Bf4, Nf3, e3, Bd3, Nbd2, c3, castling — repeats almost identically no matter how the opponent replies.

Black's three most common setups

• 1...d5 (classical) — after Nf6, e6, Bd6 Black offers to trade bishops. Instead of trading, you retreat the bishop to g3: it stays active on the b8-h2 diagonal and aims at Black's kingside.
• 1...Nf6 with a fianchetto (...g6) — Black prepares the bishop for g7, aiming at your center along the long diagonal. The strong c3-d4-e3 pawn chain blocks that diagonal for a long time.
• An early ...c5 — a side strike at the center. The c3 pawn supports d4, so you don't need to worry about the trade: after cxd4 exd4 you have a solid center and comfortable play.

Honestly, about this page's scope

The above is a sketch of the system, not a full trainer with every branch. The full London System repertoire — with all typical Black setups and an exact evaluation of every line verified by the Stockfish engine — is waiting in the opening trainer inside the app. Before playing your first opening, it's also worth knowing the 5 rules that win most games — the London System is just one way of putting those rules into practice.

More openings (including the Italian Game, French Defense, and Queen's Gambit) are covered on the Chess Openings page. Want to practice these same principles right away against an opponent? Play a game against the computer at any difficulty level.

The trainer works offline after your first online visit on this device. No app installation required.