Q. My colleagues in marketing add a full space before and after a hyphen rather than using a dash without spaces. I agree with CMOS on the proper uses of hyphens, en dashes, and em dashes, but haven’t seen any direction about the spaces before and after these characters. I tend to kern a little air between the beginning and end of a dash if the font jams them together, but it is nothing remotely close to a full space.
A. Please see CMOS 2.14: “For an em dash—one that indicates a break in a sentence like this—either use the em dash character on your word processor or type two hyphens (leave no space on either side).”