Are chapter headings and other semantically smaller parts as the title capitalized?

Solution 1:

According to CMoS and APA (two popular style guides), some lower-level headings aren't capitalised in headline-style.

Chicago Manual of Style 16th edition (headings by level):

1. Centered, Boldface or Italic Type, Headline-style Capitalization
2. Centered, Regular Type, Headline-style Capitalization
3. Flush Left, Boldface or Italic Type, Headline-style Capitalization
4. Flush left, roman type, sentence-style capitalization
5. Run in at beginning of paragraph (no blank line after), boldface or italic type, sentence-style capitalization, terminal period.

APA (headings by level):

1. Centered, Boldface, Uppercase and Lowercase Headings
2. Left-aligned, Boldface, Uppercase and Lowercase Heading
3. Indented, boldface, lowercase heading with a period. Begin body text after the period.
4. Indented, boldface, italicized, lowercase heading with a period. Begin body text after the period.
5. Indented, italicized, lowercase heading with a period. Begin body text after the period.