The Carlsbad pawn structure refers to the formation that arises usually, but not exclusively, from the Exchange Variation of the Queen’s Gambit.
It can also be reached from other Queen’s Pawn openings such as the Nimzo-Indian and Grunfeld.
We find the same structure, but this time with reversed colors, in the Exchange Variation of the Caro-Kann.
The Carlsbad structure
Probably the most popular plan for white here. The idea is to start a pawn storm on the queenside in order to create weaknesses in Black’s camp. After playing b4 and b5 (with or without a4), the c6 and a7 pawns will become weak and white will have clear targets of attack;
The second plan (one of Kasparov’s favorites in this structure!) is to play in the center and achieve the break e3-e4. White usually prepares this by playing f2-f3 first, so that he can control the whole center after an exchange on e4.
Black, on the other hand, should try to create counterplay on the kingside and/or stop white’s minority attack. He can do so in several ways:
He can play a5 with the idea of exchanging the a-pawn for white’s b pawn. This prevents white’s plan of creating two weaknesses on the queenside;
In order to do so, black must be ready to meet white’s b5 with cxb5 and a5 after axb5. This idea is usually executed with a knight on b6 that’s ready to jump to c4 and obtain the initiative on the queenside;
One last idea is to try to get rid of any potential weaknesses on the queenside. He can play Rc8 and a6 in order to meet b5 with axb5 followed by c5.
In the next example, we can see how Karpov uses the minority attack in order to weaken black’s structure. A key moment of the game is white’s move Na5 before executing the typical b5 break.
By doing so, he controls the square c5 and prevents black from playing …c5 himself. On the other hand, black correctly sought counterplay on the kingside and even had one chance of taking the advantage. However, after missing this moment, Karpov stopped his attack and went on to win the game.