This review covers the major systems of human physiology. The review is not ex­ haustive; it assumes that the student has completed a course in human physiology and wishes to refresh their memory in preparing for an examination. The student is advised to refer to a competent textbook several times in this review. This book is a revised version of a review book used by our medical students for over ten years. Coverage of the various topics in physiology is comparable to the percentage of questions on those topics in recent National Board, Part I examinations. Review questions follow every few pages of text in order to monitor your under­ standing of the just preceding material. The multiple choice questions are mainly of the two conventional types; "single best answer" questions, for which you choose the single best answer, and "multiple correct answer" questions, for which you choose the one or more correct alternatives. The two multiple choice formats have been standardized throughout the book.