Joe Schwarcz is the director of McGill University's Office for Science and Society, and he also hosts a popular radio show in Canada, in which he answers questions about science he has posed to his listeners. "Dr. Joe and What You Didn't Know" is the fourth in a series of books in which his answers are compiled. (The previous three have also been Hal's Picks.) Professor Schwarcz found that, at the time this book was being compiled, the quality of the answers his listeners were providing indicated that they had suddenly become more science-literate. This coincided with the availability of Internet search engines such as Google. Of course, he was asking his questions of the collective wisdom of the Internet, rather than his listeners. Consequently, he began to construct the questions in a way not conducive to Google searches. For example, he might ask "What common metal was once more valuable than gold?", rather than "Why did aluminum fall a hundred times in value during the 19th century?" His books are very attractive to me, both as a chemist interested in science in everyday life and as a teacher of chemistry. Like Hal's Picks, Professor Schwarcz does not limit himself exclusively to chemical topics, but his little essays consistently bring the insights of a chemist to the question at hand, and he does not hesitate to get into the chemical details of an answer that are necessary for a proper explanation. I still wish that he would include a few molecular structures in his books, and I ought to compile my own list of essays that would enhance the courses I teach, so that I would not neglect to bring them up when they fit.