BISAC stands for Book Industry Standards and Communications. Sometimes referred to as a Book Industry Subject and Category code, BISAC codes are numbers assigned to books to more easily categorize them for retailers, distributors and libraries. When you fill out the Books in Print form, youll be asked for three BISAC codes that best describe your books subject. Baker & Taylor, one of the major book distributors, also requires them if you register a title with them. You can review and choose BISAC codes at the Web site for the Book Industry Study Group (http://www.bisg.org/standards/bisac_subject/major_subjects.html). If youre not sure what code best fits your book, check out similar books at your bookstore or library and see what codes were chosen for them.