I first bought this little book in 1973 (the Penguin edition) for $1.45! I still own that same copy today, though a new edition has finally been made available to the hungry chess public (it was out of print for many years).
The first section by Golombek is nothing to crow about (though lower rated players will get something useful out of it), but things pick up when Kotov examines “Strategy and Tactics of Attack on the King and “Various Pawn Positions in the Center (these sections will be enjoyed by Class B and A players).
What makes this a must buy, however, are the two Keres offerings: “How to Defend Difficult Positions and “The Art of Analysis. Both of these sections (by Keres) are advanced, and I think that players of expert strength and higher will get the most out of them (actually, “The Art of Analysis is for senior masters, IMs, and grandmasters). At just a few bucks for 238 instruction-filled pages, this may well be the best deal you will ever get when it comes to spending your chess book buying dollar!