I bought this book last week and almost finished reading it.
It's a fantastic book, I think definitely a "must-have" for people who want to improve. At least I,m really enthusiastic about it.

Strange that it lasted for over 50 years that this fantastic book is translated into english language. It's a real chess classic!

To give an indication, in my humble opinion, for players with level of about 1900 rating up to grandmaster level. But also players below under 1900 can of course learn a lot from it.