How to build an opening repertoire

An opening repertoire is simply the set of openings you have decided to play. Without one, every game starts with improvisation, and you spend time and energy in positions you have never seen. With one, the first ten moves become familiar ground and you reach the middlegame in positions you understand. A good repertoire for a club player does not need to be large. It needs to be yours, and it needs to be learned properly.

Three decisions, not thirty

At its core a repertoire is three choices: what you play as White, what you play against 1.e4 and what you play against 1.d4. Other first moves such as 1.c4 and 1.Nf3 matter too, but you can often meet them with the structures you already use against 1.d4, and you can deal with them once the main choices are in place. Make those three decisions first.

Choosing a first move as White

• 1.e4 leads to open positions with early contact between the pieces. It suits players who enjoy tactics and attacking play, and it teaches a lot about piece activity. The cost is that Black has many replies, from 1…e5 to the Sicilian, French and Caro-Kann, and you need an answer to each.
• 1.d4 usually leads to slower, more strategic games in which pawn structure matters more. Black’s replies are varied here too, from 1…d5 to the Indian defences, but the positions tend to change less quickly, so a small gap in your knowledge is less often punished at once.
• A system such as the London System (1.d4 followed by Bf4, e3, Nf3 and c3) uses a similar set-up against almost anything. It saves study time, which makes it popular with players who have little of it. The trade-off is that you meet fewer kinds of positions, and prepared opponents know what is coming.

There is no wrong answer. Choose the kind of position you would like to reach, not the opening a famous player happens to use.

One answer to 1.e4, one to 1.d4

As Black you need a reply to each of the two main first moves. Against 1.e4, the common choices are:

• 1…e5, the classical reply, leading to the Italian Game, the Ruy Lopez and other open games. You also need to be ready for several white gambits.
• 1…c6, the Caro-Kann Defence, solid and structurally clear: 2.d4 d5 challenges the centre at once.
• 1…e6, the French Defence, which accepts a slightly cramped position and counter-attacks White’s pawn chain with …c5.
• 1…c5, the Sicilian Defence, the most combative reply but also the one with the most theory to learn.

Against 1.d4, the main split is between 1…d5, which leads to the Queen’s Gambit Declined after 2.c4 e6 or the Slav Defence after 2.c4 c6, and 1…Nf6, which leads to set-ups such as the Nimzo-Indian (2.c4 e6 3.Nc3 Bb4) or the King’s Indian. If you like solid, classical structures against 1.e4, a classical choice against 1.d4 usually fits well, but that is a preference rather than a rule.

Depth before breadth

The common mistake is to collect openings: a new defence every month, five moves deep in each. It is far better to go deep in a few. Learn the main line of each choice until you know not only the moves but why they are played, then add the sidelines you actually meet. Only after that is it worth adding a second weapon.

Depth also means knowing the middlegame plans that follow. Understanding that in the Caro-Kann Advance (1.e4 c6 2.d4 d5 3.e5 Bf5) Black usually follows up with …e6 and …c5 to attack White’s pawn chain is worth more than three extra moves of theory you will rarely reach.

Review before you forget

Lines you studied once fade quickly, especially the ones that rarely appear in your games. Spaced repetition handles this well: each line comes back just before you would forget it, a line you get wrong returns sooner, and a line you know well waits longer. A few minutes of review a day keeps a whole repertoire alive far better than an occasional long session.

Check it against real games

A repertoire on paper and a repertoire in practice are not the same thing. Two checks are worth doing regularly:

• Your own games. Look at where you actually left theory. If you keep going wrong at the same move, that is the line to review next. If opponents keep choosing a sideline you have not prepared, that is the gap to fill.
• Your opponent’s games. Before a league match or tournament game, look at what your opponent plays in the opening. If they always answer 1.e4 with the French, an hour on your line against the French is time well spent.

Start small, then grow

A first repertoire can be as simple as the London System as White, the Caro-Kann against 1.e4 and the Queen’s Gambit Declined against 1.d4. Play it, review it, look at where your games leave the book, and fill the gaps one at a time.

On TheoryChess you can browse the openings catalogue, train each line against Stockfish with an explanation for every theory move, and let spaced-repetition reviews schedule the practice. Each opening has its own quiz, such as the Caro-Kann quiz, to test what has stuck. The game reports compare your Lichess or Chess.com games, or an opponent’s, with opening theory, so you can see exactly where your repertoire holds and where it needs work.