This textbook is related to a course that the author taught for many years at University of California, Berkeley. The course was originally intended for graduate students in the biological and health sciences. But it attracted students form other departments on the campus as well. In order for the book to serve the interest of a larger audience, the author made revisions of the outline, added new topics, and provided more examples for illustrations wherever needed. This invaluable book systematically presents fundamental methods of statistical analysis: from basic probability and statistical distributions, through fundamental concepts of statistical inference, to a collection of methods of analysis useful for scientific research. The text is rich in tables, diagrams, and examples, in addition to theoretical justification of the methods of analysis introduced. Each chapter has a section entitled "Exercises and Problems, " to accompaning the text. There are altogether about 300 exercises, whose answers are given. A section entitled "Proof of the Results in This Chapter" in each chapter provides interested readers with material for further study.