To celebrate the 100th anniversary of the publication of Margaret Floy Wash-burn's (1908) The Animal Mind: A Text-book of Comparative Psychology, the book is reviewed and compared to contemporary comparative texts. Although considerable advances have been made with respect to topics, methods, and findings, of course, the original text remains remarkably relevant, both as an introduction to animal ... [Show full abstract] psychology and as a marker of changes in the discipline that spanned the book's four editions. (1871–1939) was a remarkable psychologist, best known for being a pioneer for her gender in our discipline. Besides being the first American woman to receive a PhD in psychology (from Cornell University, 1894), she was also the second woman elected president of the American Psychological Association (1921) and the second woman welcomed into the National Academy of Sciences. In truth, she was a pioneer in our discipline regardless of gender, reflecting the exciting time in which she lived in the history of psychology, combined with her aptitude, interest, and determination (as described in her delightful autobiography, numerous excellent biographies, and several stirring obituaries, e.g. Woodworth, 1948). Convinced that the new field of experimental psychology offered the opportunity to pursue her interests in science and philosophy (Washburn, 1930), Washburn studied for a year at Columbia University with Cattell before moving to the 1 Notwithstanding identical last names and common interests in the mental competencies of animals, including humans, the present author is not (so far as I know) related to Margaret Floy Washburn. Given how frequently I am asked the question, and inspired by two new courses that I taught this year (a graduate history of psychology course and an undergraduate honors seminar called "Animal Minds"), the present review was undertaken to mark the centennial anniversary of Professor Washburn's most influential publication by recommending it to the new generation of comparative-cognition researchers.