The Closed Sicilian has been a popular opening on the tournament level for over 40 years. Made popular by former World Champion Boris Spassky, it leads to very different positions than the Open Sicilian. White will not try to open the position with an early d2-d4 pawn advance and often no pieces are exchanged for over 10 or 15 moves. White will usually try to gain a space advantage on the kingside and try to attack Black’s castled king. Sometimes White may even opt to castle on the queenside, though this is not without risk since this is usually where Black’s strongholds lie. In the Closed Sicilian, Black’s main goals are maintaining control of the d4-square and trying to penetrate into White’s position via the queenside.

2.Nc3 leads to the Closed Sicilian. White will try to keep the center closed for now and maintain a grip on the e4 and d5- squares. When the center is closed, it is less risky to attack the opponent’s king on the flanks of the board.

2…Nc6 is by far the most popular move here. Black now has a firmer grip on the dark center squares d4 and e5. Black sometimes plays 2…e6 with the idea of playing 3…d5. White cannot prevent this, but should continue like in our main line on moves 3 and 4.
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The Closed Sicilian does lead to fewer tactics early in the game and does not require a vast amount of opening knowledge.

3.g3 is a subtle move that prepares to fianchetto the f1-bishop to g2. From there it will add to the control that White already has over the d5-square. One may ask if it wasn’t simpler to play 3.Bc4. But on c4, the bishop could soon be attacked with …e6 and …d5 or even …a6 and …b5. 3.f4 is a common alternative to our text move and is a bit more aggressive than our line of play.

Black sort of emulates White by also preparing to fianchetto his kingside bishop with 3…g6. This will give Black added control over the d4-square.
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White would continue in the same manner if Black varied early from our line of play.

4.Bg2 gets the bishop to its ideal Closed Sicilian square. From g2 it eyes d5 and will also give some shelter to White’s king should it castle on the kingside. Note that 4.d3 or 4.f4 often transposes to our line of play.

4…Bg7 is the natural move for Black, since there are no pressing issues to address yet.
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Note that there is no contact between the two armies yet. Hence, play is less forcing than in most Open Sicilian positions.

5.d3 opens the c1-h6 diagonal for the other bishop and is a solid and natural move here.

Black still emulates White’s setup by playing 5…d6. Reasonable alternatives are 5…Rb8 (with the idea of playing …b7-b5 next) and 5…e6. White should meet both with 6.Be3.
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White will usually try to gain control of the d4-square right after the first 8 to 10 moves.

6.f4 is a popular move here and gains more space on the kingside. The main alternative is 6.Be3, when White typically aims for 6…e6 7.Qd2 Nge7?! 8.Bh6 with chances for an early kingside attack after 8…0-0 9.h4.

6…e6 prepares for the development of the g8- knight to e7. Should Black develop the knight to f6 instead, White will typically play h2-h3 right after and then try to attack the knight after kingside castling with g3-g4.
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Control over the f5-square often makes or breaks a White kingside attack in the Closed Sicilian.

7.Nf3 only moves this knight into the action after the f-pawn has already moved to f4. Now White has some control over e5 and will soon try to fight for d4 as well. White has tried other plans with 7.Nh3, 7.Rb1, 7.Nge2 and 7.Bd2, while 7.Be3 may lead to similar lines later.

7…Nge7 achieves a flexible setup for Black and does not move this knight in the way of the g7-bishop. This has become the more popular way to bring the g8-knight into play against White’s setup. The traditional route to f6 has the drawback that White can often achieve a pawn avalanche on the kingside by playing h3, g4 and f5. Should White now try the same plan, Black will be ready to meet g4 with …f7-f5 himself and stop White immediately.
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With best play Black does achieve equality in the Closed Sicilian.

8.0-0 gets the king to safety and the h1-rook into play. The main alternative, 8.Be3, will often transpose soon.

Black also improves his position by castling kingside with 8…0-0.
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The battle now intensifies as both sides will soon seek confrontation.

9.Be3 is the most popular move here. From e3, the bishop eyes d4 again and threatens to advance the d-pawn to d4 next. White would then have a clear space advantage in the center. Main alternatives here are 9.Bd2 (with the idea of Rb1, a3 and b4) and 9.Rb1 (with the idea of playing Ne2 soon or above plan from 9.Bd2).

9…Nd4 moves the knight to d4 and thus stops White from pushing the d-pawn to d4. This is Black’s normal means to keep control over the key d4-square. Instead both 9…b6 10.d4 Ba6 11.Re1 and 9…f5 10.e5 are better for White.
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Black will not relinquish control over d4 without a fight.

10.e5 became very popular in the 1980s. Initially Black had great difficulty equalizing. After 10…Nf5 11.Bf2 dxe5 12.fxe5 Nxe5 13.Nxe5 Bxe5, Black has temporarily won a pawn. But White could then regain it with a fine position after 14.Ne4 Qc7 15.c3, and the c5-pawn would fall. This continuation is still popular with White players as it is hard to lose with it. 

10.Qd2 moves the queen to the typical square in this opening. Now the queen forms a nice attacking unit with the bishop on e3 (should White ever be able to play f4-f5). Note that the a1-rook could next move to e1 and join the complex battle. White may then play Nd1 and c3 in order to force the d4-knight to leave its nice outpost. The main alternative here for White has become 10.e5. After 10…Nf5 11.Bf2 dxe5 12.fxe5 Nxe5 13.Nxe5 Bxe5, Black has temporarily won a pawn. But White could then regain it with a fine position after 14.Ne4 Qc7 15.c3, and the c5- pawn would fall. After 10.Qd2, play is usually a little less tactical than after 10.e5. Black will typically continue with either 10…Nec6, 10…Rb8 or 10…d5. 10…Rb8 is best met with 11.Re1 b5 12.Nd1, while 10…d5 is best met with 11.Bf2. 
After 10…Nec6, White also has several plans to choose from. The game Arapovic-Cebalo (1988) continued with 11.Nd1 Nxf3+ 12.Bxf3 Rc8 13.c3 b6 14.h4 Bb7 15.Qg2 Re8 and an uneventful draw not too long after. Another idea was demonstrated in Yudasin-Har Zvi (1997): 11.h3 f5 12.Kh2 Bd7 13.Rab1 Rb8 14.a3 b5 15.b4 Nxf3+ 16.Bxf3 cxb4 17.axb4 with unclear play. Note that in the last game, White was able to divert Black’s c5-pawn with the b4-pawn. Thus Black’s grip on the d4-square weakened considerably. In general, play after 10.Qd2 Nec6 is of positional nature and often features long maneuvers before one side can claim a clear advantage. Tactical motifs will become increasingly important in the middle game as both sides pursue their own plans. Should you not like these positions for White, you have plenty of alternatives to look at on move 2.