The idea of meeting Black’s queenside fianchetto with a kingside fianchetto in order to neutralise the pressure of the Bb7 along the a8-h1 diagonal by the Bg2 has been the main line of the Queen’s Indian Defence since the early days back in the 1920s. The list of the players who have had confidence in this setup stretches from Capablanca, Alekhine, Euwe and Smyslov all the way to Karpov and Kramnik, to name only world champions.
Black has above all – as was the case against the Petrosian Variation – the choice between 4...Bb7 and 4...Ba6, though occasionally 4...Bb4+ is played. In modern grandmaster chess 4...Ba6 is popular, a move which had already been played in 1925 by Nimzowitsch, but to which little attention had then been paid.
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