Before you lies the second volume in a trilogy about the Sicilian Defense. The first volume dealt with the Najdorf and Scheveningen variations, and it is now time to pay attention to three other extremely popular systems: the Taimanov, Kan and Richter-Rauzer variations. After careful consideration within the Thinkers Publis -hing team, we decided that it made sense to group these variations together. In particular, the first two are closely related and share the feature that, in both cases, Black plays ...e7-e6 and ...a7-a6 at an early stage. They typically have the idea of retaining more options for their king's bishop by postponing ...d7-d6 (or even omitting it entirely.) The bishop may go to b4 or c5 in different lines. The Richter-Rauzer is, in theory, just one of the possible developments from a Classical Sicilian. We have already dealt with a few games that started with the Classical and where Black shortly played ...e7-e6; and 6.Bc4 (the Sozin variation) was rightly treated within the Scheveningen pages. However, it is clear that White's most po pular counter, the Richter-Rauzer variation (6.Bg5) deserves separate attention. While looking at the variation structure for the Kan and Taimanov and deciding on which model games to use, I noticed a lot of possible transitions to the 'Hedgehog' structure, shown on the right. The key features are white pawns on e4 and c4, and at least four black pawns on a6, b6, d6 and e6. This structure is ideally suited to the task of playing for a win as Black, because of the very complicated middlegames that arise. (And one often needs complicated middlegames to have a better chance of 'converting' a rating advantage!) The 'Hedgehog' is definitely a structure rather than a variation, but it has such a distinctive character of its own that I chose to examine it first in chapter 2. This simplifies later discussion of the Taimanov and Kan variations by removing the need to discuss every possible way of entering a Hedgehog structure.