"The book is a self-contained one and there are … complete proofs for all the results. In our opinion, it is a highly recommended introductory book in Homological Algebra for everyone interested in this subject."- Zentralblatt MATH, 1045"… [T]he author on the one hand has included the underlying basics, model and category theory, which are developed from scratch. On the other hand the elementary notions and results of homological algebra are treated in great detail and often their importance within that theory as well as in applications is shown. … All in all the author has managed … admirably to reach the goal he has set [for] himself."- Monatshefte fur Mathematik"When I next teach an introductory course on homological algebra at my institution, I will certainly consider adopting this book as the textbook for the course.-Mathematical Reviews