In the preface of this book, the authors express the view that 'a good working knowledge of injective modules is a sound investment for module theorists'. The existing literature on the subject has tended to deal with the applications of injective modules to ring theory. The aim of this tract is to demonstrate some of the applications of injective modules to commutative algebra. A number of well-known concepts and results which so far have been applicable principally to commutative rings are generalized to a non-commutative context. There are exercises and brief notes appended to each chapter to illustrate and extend the scope of the treatment in the main text. Together with the short bibliography the notes form a guide to sources of reading for students and researchers who wish to delve more exhaustively into the theory of injective modules. The tract is intended primarily for those who have some knowledge of the rudiments of commutative algebra, although these are recalled at the outset.