This book is designed as a manual for the study of fundamental moral theology. It is addressed primarily to those who are undertaking a required course of study in Catholic theology at seminaries or ecclesiastical colleges. The editorial and typographical style, the choice of topics, and the extent of material covered are intended to meet the needs of such students. Nevertheless, we trust that the book will likewise be of interest for those who pursue theological and moral studies at a non specialist, though nonetheless serious level.