This book provides an elementary course in the theory and the application of annuities certain and in the mathematical aspects of life insurance. The book is particularly adapted to the needs of students in colleges of business administration, but it is also fitted for study by college students of mathematics who are not specializing in business. Annuities certain and their applications are considered in Part I, life insurance is treated in Part II, and a treatment of logarithms and of progressions is given in Part III. The prerequisites for the study of the book are three semesters of high school algebra and an acquaintance with progressions and logarithmic computation. Very complete preparation would be furnished by three semesters of high school algebra and a course in college algebra including logarithms. The material in the book has been thoroughly tested by the author through the teaching of it, in mimeographed form, for two years in classes at the University of Minnesota. This still very informative and helpful book is a reprint of the original published in 1924.