Key ideas
- 3...Bf5 is the main reply. 4.Nf3 e6 5.Be2, the Short Variation, is a quiet set-up with O-O and c3 followed by slow pressure; Black develops with ...c5 or ...Nd7 and ...Ne7.
- The sharp lines go after the f5 bishop with pawns. 4.Nc3 e6 5.g4 Bg6 6.Nge2 is the Van der Wiel Attack, and 4.h4 is the Tal Variation. Black answers with ...c5 to hit the centre while White's pawns are advancing, or with ...h5 or ...h6 against h4.
- 3...c5, the Botvinnik-Carls Defense, attacks d4 at once. Black spends a second move with the c-pawn but gets a French-type structure in which the light-squared bishop is not yet shut in.
- With the bishop outside the chain, Black's play resembles a French Advance with its problem piece already solved: ...e6, ...c5, ...Nc6 and ...Qb6 against d4. The price is time, because the c-pawn often moves twice.
Plans for White
Either play slowly and use the space (Nf3, Be2, O-O, c3) or chase the bishop with g4 and h4 before Black finishes developing. In both cases the e5 pawn keeps Black's knight off f6.
Plans for Black
Develop with ...Bf5, ...e6, ...Nd7 and ...Ne7, then strike with ...c5. If White pushes g4 and h4, the bishop retreats to g6 or e4, and ...c5 or ...h5 counters the advance.
For the wider picture, see the Caro-Kann Defense guide.