This is the original classic work of Bronstein. Recommended by so many master players that improving players should study. Too often the book is quoted as a great classic without a realisation that later versions of this book are just a butchering of the original. So avoid the reprint by Dover publications as it is truly awful. This is the second edition and is a slightly worse than the first print. This version is true to Bronstein's goal. He set out to create a middlegame study work from the tournament 1953 event. The Zurich 1953 tournament was the tournament setup to find a challenger for World Champion Mikhail Botvinnik and as such featured the worlds best players bar Botvinnik himself. Botvinnik as an author is superb at communicating the ideas of the specific position and identifies each important moment in the critical games. This version of the book is a must study for any improving chess player and is a true classic.