'This book is excellent in many respects. It is beautifully written, it contains many new and clever arguments, and it is a long, connected story told by a masterful storyteller. … Operator semigroup theory continues to grow and thrive and new and unexpected applications continue to lead to new theory. There is a large textbook/monograph literature including the early book by Hille and by Hille and Phillips, and later books by, alphabetically, Cialdea and Maz'ya, Davies, Dunford and Schwartz, Engel and Nagel, Fattorini, Goldstein, Kato, Krein, Lax, Nagel et al., Pazy, and Yosida. Bobrowski's book stands with these as books which contain information about theory and applications which could not be found elsewhere at the time of publication. Bobrowski's superb exposition and his wide scope and new applications will keep the semigroup community busy. We can all be grateful.' Jerome A. Goldstein, Semigroup Forum