"Popular science books" can contribute to enhancing public engagement with chemistry, yet there has been no systematic study of the availability, use, and educational significance of these books. This paper identifies titles in the catalogues of some major publishers, the content of these books, the criteria that readers might use in judging their educational worth, and the value of these categories of books for promoting public engagement with chemistry. One hundred and ninety-three popular chemistry books, written in English and/or Portuguese, were identified in the catalogues of 80 major publishers. This identification and classification into themes were carried out by an analysis of synopses and introductions. In addition, an opportunity sample of 17 Portuguese undergraduate students, with no extensive backgrounds in science, was invited to produce a written evaluation of a book of their own choice. The producers of unusual or incisive evaluations (nine readers) were also interviewed. It was found that popular books can contribute to public engagement with chemistry when they have specific textual characteristics. There is a need for more books in Portuguese, and for more titles in specific fields, in order to broaden readers' perceptions of the cultural value of chemistry.