What are you supposed to do at this point in the London System as White?

The theory on the opening says that 4. e3 is fine, but what if the opponent goes 4. ...Nh5 ? Isn't this bad for white?

If I go 5.Bg3, they'll likely capture the bishop (5. ...Nxg3), which makes me lose a good bishop AND have doubled pawns.

Or instead if I ignore the knight and just develop with 5. Nbd2, the opponent can just take on f4 and leave me with doubled f pawns.

The other question I'd like to ask you is regarding this other position in the London: lichess.org/study/MJFhnm1X/150Ss4HH#14

After 7. ...Bd6, is capturing the black bishop forced? Otherwise black captures my bishop and, again, gives me doubled f pawns. But if I capture the black bishop first (8. Bxd6), I help the black queen get active.

I'd appreciate your feedback :)

After Nh4 I'd ask to reset the pieces so I could play a real opening.

After Bd6, In similar positions I've allowed the doubled pawns so there's some imbalances with which I can build an initiative; d4 is relatively safe.

But on a more serious note, Black has several ways to comfortably equalize against the London; consult the Masters opening explorer for statistics.

Thanks. I've delved a bit more into these lines in the meantime. Found out that in the first variation I could also play 5. Bg5. I like it even more than Bg3. Initially I was afraid of ...f6 followed by ...g5 in response, but it doesn't work because I can capture on g5 with the knight and if black recaptures, the black knight is hanging.



...h3 followed by ...g5 works for black, but then there is Nfd2! with the discovered attack on the black knight! I totally missed that move before. Black is then forced to retreat his knight to g7 or f6. If he was adamant on taking my bishop with the pawn, then I capture his knight with my queen, which makes him end up with double rook pawns and me having an active queen.

So black can't just push ...h3 followed by ...g5 with tempo. He does get a lot of space on the kingside, but also he can't castle kingside so safely now. I really like this position from that point onwards.

Also in the second variation someone else told me that 8. Ne5 is pretty good. Now if black captures on e5, I can occupy the e5 square with either a bishop or pawn, and control the e5 square.

Not sure how the concrete theory goes here, but ...g5 Nfd2 ...Ng7 Bg3 ...Nf5 still snatches the Bishop, followed by Bg7. This is considered completely ok in the majority of cases.

Yes, this is true. At least in that case you get a tempo to e.g. push c4 while black captures the bishop. And black gets more space on the kingside, but now has minor light square weaknesses. I suppose it's fine for both sides.

"If I go 5.Bg3, they'll likely capture the bishop (5. ...Nxg3), which makes me lose a good bishop AND have doubled pawns."
Your good bishop is the one not on the color of your pawns. Your bad bishop is the one on the color of your pawns. So Bf4 is your bad bishop and Bf1 your good bishop. So it is not that bad you lose Bf4. Doubled pawns are not necessarily bad. You get an open file for your rook.

In your 2nd example 8 Bxd6 trades your bad bishop for his good bishop. You can also play 8 o-o, as the doubled pawns are OK. Of course 8 Ne5 is good too.