The Index as a Map to the Book’s Content
by Mary Harper


MaryIt is often said that a book without an index is like a country without a map. Imagine you wanted to visit Aunt Helen: you know she lives in Seattle, you know her street name and number, but if you have no map of the city, how do you find her?

Just as a map of Aunt Helen’s city and neighborhood will help you locate her, an index will help you locate vital information within a book. Basically, an index serves five functions:

1. It encourages efficient retrieval of topics;

2. creates a map of the author’s message with succinct entries;

3. groups together concepts that are scattered throughout the text;

4. creates interrelationships between explicit and implicit concepts; and

5. can function as a decisive factor in book selection or purchase.


What is Included in an Index?

An index is an efficient information retrieval tool,  especially where detailed information is important. Nancy Mulvany, author of Indexing Books, wrote: “An index is a structured sequence—resulting from a thorough and complete analysis of text—of synthesized access points to all the information contained in the text. The structured arrangement of the index enables users to locate information efficiently.”

Here are two examples of what are sometimes referred to as indexes. The first is a actually a concordance rather than an index, and is simply a listing of page numbers for a term found in the text. This type of list can be auto-generated by software. The second example is of a Subject Index, created by a professional indexer.



New Deal era, 5-9, 16, 17-18, 31, 43,

45, 54, 64-65, 68-72, 78, 88, 101,

105-108, 265-270


Subject Index

New Deal era

…banking crisis intervention, 5-9

…Civilian Conservation Corps, 265-270

…Farm Security Act, 16, 54

…recession of 1937, 31, 101

…Rural Electrification Administration, 88

…securities regulation, 105-108

…Social Security System, 45, 68-72


Think back to that map: If you were looking for Aunt Helen’s house, which would make it easier for you to find it? If you were a reader looking for the passages on securities regulation, the Subject Index would lead you right to it, without the need to thumb through many, many pages.


Index audiences

In general, there are two audiences for a book index. One is someone looking to determine if the topics they are interested in are in the book before reading or purchasing it, the other is someone who has read the book already and wants to find the page numbers of certain topics they recall or want to research further.


Does My Nonfiction Book Really Need an Index?

If you or your client have hopes that a nonfiction book will be sold commercially or be included in a library collection, there are even more reasons to include an index. We give any nonfiction author these three: (1) Book reviewers often look for the inclusion of an index as a sign of quality—this author has paid attention to details! (2) The library market expects a nonfiction book to have an index. (3) Indexes can help increase sales, both online and in the store.

We all have observed people in a bookstore browsing through an index to help them decide whether the book contains the topics they’re interested in. Think about how information-laden our lives have become and how useful an index is to someone who feels short on time. For books sold online, being able to browse the inside of a book—which often includes the index—contributes to sales. Amazon has noted that books using their “Look Inside!” feature are significantly more successful than books that don’t use this feature.

Regarding the selection of your book for a library, Robert Broadus said in a text on library book selection criteria that “a good index should be expected in any work except creative literature.” Richard Gardner, founding editor of CHOICE, a publication of the Association for College and Research Libraries, had an even stronger admonition: “Publishers need to be told that nonfiction works without an index are practically useless in libraries and in the long run will lose sales.” And for S. R. Ranganathan, an early expert on library book selection, “to get into a book without an index is like getting into a forest without a trained guide.”


Name Indexes

In addition to Subject Indexes, some books benefit from a name index.  I once created the index for a family history that started in 1700s Ireland. There were seventy-seven individual Kelly family members discussed in the text and many, as was the naming custom, had the exact same names. The author and I agreed it would be best to distinguish the various people with birth and death dates. I had to sketch out the family tree to keep all the generations straight. In this situation the indexer may need clarification from the author about the exact relationships between people.

In a Name Index parenthetical identifiers are often used to make the index even more useful. This is especially needed when like the example above there are many people with the same surname and the same or similar given names.

Names Indexes present other challenges such as treatment of birth and married surnames for women, name changes as a result of entering religious orders, pseudonyms, and nicknames. Sometimes only the surname is available and you may need to identify the person for example as “Johnson, Miss (teacher)” or “Clara, Aunt.”

Also, naming conventions vary greatly in different languages and cultures, and an accurate observance of these conventions should be reflected in the index. The Chicago Manual of Style has some basic guidelines on international naming customs.


Can You Create Your Own Index?

No one knows a book like its author, but authors are often so immersed in their subject that they find it difficult to analyze the text from the readers’ standpoint. Usually the author does not have training or tools, nor will they be familiar with current indexing conventions. A professional indexer will bring a fresh eye to a project, careful thought about the author’s message, and the ability to keep the whole project in his/her head at all times.

Some indexers, like myself, even provide a complimentary report of typos and formatting errors that they happen to notice while indexing and I have yet to index a text without some findings. But, keep in mind that this service cannot take the place of formal proofreading or editing.

As Olav Kvern and David Blatner, authors of the Real World Adobe InDesign series, observed, “Sitting down and indexing a book is—in our experience—the most painful, horrible, mind-numbing activity you could ever wish on your worst enemy. And yet, where this is the kind of task that a computer should be great at, it’s actually impossible for a computer to do a good job of indexing a book by itself.”

Fortunately, there are indexers out there who relish the intellectual challenge of organizing the terms and concepts spread throughout the text into a structured, efficient tool.


How Are Indexes Priced?

The cost of an index is typically set on a per-page basis. The page rate varies depending on several factors including: (1) density of text (expected number of index entries per page); (2) complexity of material (technical terminology, footnotes, etc.); and (3) page and font size (as these are book, not manuscript pages). The indexer prefers to preview a chapter or two from the midsection of the book to evaluate these factors before giving a firm quote. Rush deadlines sometimes incur additional fees, so giving the indexer ample lead time will help keep your costs down and help ensure you receive the highest quality index.


Learn More About Indexes and Indexers

To judge or write a quality index, the “Index Evaluation Checklist” is a useful resource and can be found at this American Society for Indexing web page:

For information on naming conventions, I recommend Indexing Names, published by the American Society for Indexing: A free resource for international naming conventions is from the Human Rights Information and Documentation Systems International titled How to Record Names of Persons:

You can find an indexer at the American Society for Indexing, ASI Indexer Locator ( Links to other internationally based indexing societies can be found there also.

If you have a quick question about indexing, send me an email to [email protected].


Mary Harper of Hood River, Oregon. Her business is Access Points Indexing, which produces indexes for print and ebook publication. She has created over 300 indexes in many varied subjects. Contact for a free estimate.