Statistics lectures have often been viewed with trepidation by engineering and science students taking an ancillary course in this subject. Whereas there are many texts showing 'how' statistical methods are applied, until now there has been no textbook for non-statisticians providing a clear explanation of the underlying principles of data analysis. Data Analysis: A Bayesian Tutorial provides such a text, putting emphasis as much on understanding 'why' and 'when' certain statistical procedures should be used as 'how'. This difference in approach makes the text ideal as a tutorial guide for senior undergraduates and research students, in science and engineering.