CMOS

Q. I just bought the 17th edition. Do you know where I can find out what typeface the text is set in?

A. If you turn to the very last page of text, following the index, you will see that the print edition of the Manual is composed (or typeset) in Lyon and Atlas Grotesk. Lyon, which has serifs, is used for most of the text aside from run-in paragraph subheads and certain illustrations. (The statement at the end of the book about design and production is called a colophon; see CMOS 1.67.) To complement the look of the printed book, CMOS Online (including the Q&A!) uses a version of Lyon designed for the screen.

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]