"Most chess players are too materialistic. So Merjin van Delft masterfully discusses a vital topic to bring your chess to the next level. It is very valuable that he has included exercises to test your new skills directly."

– Karsten Muller, Grandmaster

"The question of when to sacrifice material is never easy but here is a practical guide. The intended audience is above beginner and I would say any club player would benefit from the author's passion for the subject. The themes that are covered involves things like exchange sacrifices where the aim to not to win material but dominate certain squares, boost an attack and other positional ideas. Van Delft expertly expands on the subject to make it sound extremely interesting and as a potential way to improve your rating overnight. I really like the book because it offers insight with excellent examples and enough explanation to enable the reader to improve. This will have a major impact on your positional progress."

– Gary Lane, International Master

"The material has been carefully selected and structured, with conclusions at the end of each part. There are many fascinating games, and I saw examples I was familiar with as well as a lot of new and unknown material. This book is a testimony to the author's enthusiasm, his professionalism and his passion for chess. Recommended!"

– Herman Grooten, International Master, Schaaksite

"One gem of a book. The book is broken down into four parts. Fundamental themes, Typical positional sacrifices, Testing the limits, and Training material. Each of these sections is further broken down into chapters covering items such as opening files, pawn structure, color complexes, pawn and exchange sacs which arise from particular openings, etc. One nice thing about this book is that it's new enough to include examples from Leela and AlphaZero. Another excellent feature is the inclusion of 48 positions used as exercises."

– Chris Wainscott, On the Road to Chess Master

"It's a grandmaster-level skill explained in a comprehensible and readable fashion. I liked this book very much. The ideas are logically structured, the text is clear and light on long variations, which makes it easy to read without a board, and the theme is an interesting one, which inevitably means that the selection of games is very entertaining."

– Matthew Sadler, co-author of Game Changer

"The popular and successful Dutch coach believes that mastering positional sacrifices is a vital skill. He is certainly quite an expert on them, presenting a wide range of inspirational examples, while revealing how deadly they can be and exactly how to identify when the moment is right to be brave and make that positional sacrifice."

– CHESS Magazine