<Characteristically, the King's Indian Defense features a tense battle waged on all fronts simultaneosly. The system used here secures White considerable territory, not only in the center, but on the kingside as well.

I do not wish to leave the reader the false impression that White's further task, which is to transform his sizeable spatial plus into a material advantage, will be an easy one. The secret of the King's Indian's hardihood is that, while conceding space, Black builds a few small but weighty details into his configuration. Foremost among these are his long-range bishops at g7 and c8, his firmly entrenched knight at c5 and the rook at e8, which maintain constant watch on the e-pawn. Nor ought we to forget his pawns. The "weak" pawn on d6 is just waiting for the chance to push to d5, so White must continually keep an eye on that. The pawn on a4 also has an important role; the threat to advance it to a3 can upset his opponent's plans for that sector at any time, so White must take extra precautions regarding the defense of c3 and c4. If 12. Qc2 was White's latest theoretical discovery, then the same might justifiably be said of Black's 14...Nfd7. 14...Qa5 was the old move, but after 15. Bf4, either the bishop at g7 or the rook at e8 had to move to an inferior position, whereas now the pawn can be covered with 15...Ne5.>

and after White's 18th:

<Ståhlberg decides to rid the position once and for all of the threat of a black pawn advance to a3. This move deprives the square b3 of pawn protection, but it also strengthens the position of the pawn at b2 and generally of the whole constellation a3-b2-c3.

The next stage of the game - roughly to move 30 - consists of skilful maneuvers from both sides, inducing weaknesses, White's preparation for e4-e5 and Black's for d7-d5 or f7-f5, and mutual prevention of these breaks.>

and after Black's 23rd:

<The next two moves are somewhat unusual, both for White and for Black: Black concentrates maximum firepower against the pawn on e4, an assault which White tries to divert by threatening to take on d6. It is entirely characteristic that, in order to carry out this idea, White can find no better retreat square for his centralized knight at d4, the pride of his position, than back to its original square g1, since all other retreat square would interfere, in one way or another, with the coordination between his pieces.

This seems an appropiate time to impart to the reader the secret of the d6-pawn in the King's Indian Defence. This pawn, although backward on an open file, proves nevertheless a tought little nut to crack, because it is so hard to reach. It might seem that nothing could be simpler than dropping the knight back from d4, but the problem is that White needs his knight precisely on d4, where it observes the squares b5, c6, e6 and f5, and neutralizes the power of the bishop at g7. Only after White has taken precautions against all of Black's possible attacks (a4-a3, Bc8-e6, f7-f5) can this knight allow itself to leave the center; but meanwhile Black has time to regroup.

and after White's 24th:

<The knight will return, five moves later, to help the pawn on e4 cross the Rubicon. The pawn could have been pushed at once, but that would have given up control of the f5 square; Black's bishop could go there, and after 24. e5 Bf5, White would have had to sacrifice his queen by taking the knight on f6 with his pawn - but that would win for White. The simple 24...dxe5, on the other hand, would give Black excellent play.

White could have taken the a-pawn here, but at too great a price; White needs his darksquare bishop as much as Black does.

Boleslavsky's 24th move is an invitation to White's rook to capture that long-disputed point at last; after 25...Nb6, however, Black's knight enters c4. Ståhlberg's decision is most probably the correct one; before proceeding with the siege of the d-pawn, he exchanges off the "Indian" bishops.>

and after Black's 28th:

<The position appears basically unchanged, but an important event has taken place: the disappearance of the darksquare bishops, and of the pawns at c4 and d6. With the bishops' disappearance, both sides must now make some adjustments in their basic strategies. Black, for example, must give top priority to securing his position on the long diagonal, and against the incursion of a white pawn to f6 and queen to h6. Considering the seriousness of this threat, Boleslavsky's last move was a very good one: the bishop is ready for action on the a2-g8 diagonal, and the f-pawn, by going to f6, covers the king against any attacks from the main road; the bishop replaces the pawn at f7. White, for his part, must punch a hole in this new defensive line at any cost, or else the initiative will pass to his opponent, and all the weaknesses in White's position, which were of only passing interest so long as he was on the offensive (b3, the lack of pawn control of d3, e3 and f3, and the passive bishop at g2) might become the basis for combinations.>

1) on the game itself, I have the feeling that 12.b3 is a better way to counter Black's activity on the queenside (ready to answer a4 with b4), and I don't like Stahlber'g a3 very much