The Author Guide to Book Indexing: Chicago Manual of Style Rules and Index Formatting
Master back-of-book indexing for academic, historical, and business nonfiction. Explore Chicago Manual of Style indexing conventions, cross-referencing, and layout rules.
Julian Thorne
Senior Managing Editor
"For serious nonfiction authors, historians, biographers, and business leaders, a comprehensive back-of-book index is not an optional afterthought; it is the definitive hallmark of an authoritative reference work. Academic libraries, university presses, and discerning reviewers routinely judge the credibility of a nonfiction book by the rigor of its index. Creating an effective index requires applying the established guidelines of The Chicago Manual of Style (CMOS Chapter 16) to transform complex thematic material into an intuitive roadmap for readers."
Core Key Takeaways
- Indexing Principles: Concepts vs. Keyword Searching
- Formatting Cross-References: See and See Also
- Interior Typesetting of the Index Section
1. Indexing Principles: Concepts vs. Keyword Searching
A fundamental error made by inexperienced authors is using automated concordance tools that merely list every mention of a keyword. A true index maps ideas, analytical themes, and intellectual arguments. An entry should guide the reader to substantial discussions, arguments, and case studies, filtering out passing mentions and casual name drops.
- Main Headings: Nouns and substantive concepts (e.g., "Monetary policy," "Executive leadership").
- Subheadings: Specific thematic aspects or chronological subtopics beneath a main entry.
- Passing Mentions Rule: Exclude page references where a term is merely mentioned without informative context.
2. Formatting Cross-References: See and See Also
Cross-references connect synonymous concepts and guide readers to related discussions. The Chicago Manual of Style dictates strict formatting: "See" directs the reader from an unindexed term to the preferred heading (e.g., "Automobiles. See Motor vehicles"), while "See also" directs the reader to related supplementary entries that provide deeper context.
- Italicized indicators: "See" and "See also" are traditionally set in italic type.
- Placement: "See" follows the main heading immediately; "See also" appears at the end of the entry or after subheadings.
- Inverted names: Alphabetize personal names by surname (e.g., "Churchill, Winston").
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3. Interior Typesetting of the Index Section
Because indices require high informational density, they are typeset in smaller typography (typically 8pt or 9pt serif) in two-column or three-column layouts. Proper hanging indents (usually 1 pica or 12pt) ensure that runover lines are visually subordinate to main entries, preventing reader confusion.
- Multi-column grid: Two columns for standard 6x9 trade books; three columns for larger trim sizes.
- Hanging indents: First line flush left, subsequent wrapped lines indented.
- Letter groupings: Alphabetical dividers (A, B, C) separated by a half-line of white space.
The Takeaway
A well-constructed index transforms a dense manuscript into an enduring reference standard. Golden Ivory Publishing provides dedicated professional indexing services adhering to rigorous Chicago Manual of Style requirements.
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