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Q. When writing out a person’s title that includes a hyphen, when the first letter would be capitalized, should the word following the hyphen also be capitalized (e.g., Co-Founder)?
A. Chicago does not hyphenate co- words (CMOS 7.89, section 4), and in Chicago style, the second half of a hyphenated word that begins with a prefix is lowercased, although there are exceptions. Please see CMOS 8.161, item 3.