Despite consumer's widespread interest in reading, enjoying, and buying books, very little research has considered the critical success factors of books. This article focuses on similarities and differences between success factors when selling fiction books sequentially in hardcover and paperback form. Using a large dataset gathered in cooperation with a leading German market research institute, this work estimates a seemingly unrelated regression model and finds that key marketing considerationssuch as popular authors (stars), special genres, publisher strengths, and book cover designshave different (and sometimes conflicting) influences on sales of the same book title depending on the edition format.