It is true that common indexing wisdom is to avoid repeating locators within an array. Repetition, with locators duplicated across subheadings, can bloat an index. An array may be difficult to read, or confusing to readers, if there are too many similar subheadings side-by-side. If there is a strict length limit, there may also not be enough space for duplication.

And yet, as with many conventions in indexing, “it depends.” I recently wrote an index in which I did consider repeating locators within an array. I think it is worth teasing out why this may sometimes be appropriate.

Framing Discussions

To start, it is important to recognize that discussions can be framed multiple ways. This affects how subheadings are phrased.

One option is to state the literal concept, object, organization, or person that is being discussed. For the book I recently indexed, which was about Anglican Church leaders and fertility-manipulation schemes during the interwar period, this could be something like,

birth control: Anglican leaders on

This tells the reader who is commenting (Anglican leaders) and what they are commenting on (birth control), but it does not tell us anything about the substance of the discussion.

Another approach is thematic, to focus on that substance. For example,

birth control: class and; empire and

These two approaches can also be combined, though such subheadings can become unwieldy and each element of the subheading may not appear on every page. For example,

birth control: and Anglican leaders’ concerns about class and empire 

My point here is not to advocate for one framing over another. I use different approaches, often within the same index. It depends on what I think it most relevant for the reader and the array. To cut down on length and to keep arrays succinct, it often helps to pick a single frame. As is oft said, the goal is to point readers to the information, not to rewrite the text.

Other times, however, it may make sense to include multiple frames—multiple subheadings—because the different frames carry equal weight and because the discussions—and locators—while overlapping, are also distinct. This can help tease out the different elements, especially when discussions are complicated and intertwined. So, something like,

birth control: Anglican leaders on; class and; empire and

Alternate Entry Points

An alternative to having parallel subheadings and duplicate locators within an array is to create entry points elsewhere. Perhaps there is not enough space in the birth control array to include subheadings for class and empire, but those can both be (and should be) main entries in their own right. When considering the different elements of a discussion, and the different ways a discussion can be framed, think about what other headings and subheadings can be created elsewhere. An index is the perfect place to deconstruct and scatter discussions.

Multiple Discussions Per Page

It may also happen that a single page contains multiple distinct discussions. This is especially true the more words there are per page, depending on how the book has been typeset. If this is the case, then index to the discussions. Don’t worry if locators are duplicated. 

The trick here is distinguishing what is truly a distinct discussion or fact, rather than a granular subset of the same discussion. Does the discussion still hold together when you telescope out?

Focus on the Story

Lastly, consider the story that the array needs to tell. What is it, about this subject, that is important for the reader to know? This is not about rewriting the book in the index, but rather about effectively pointing readers in the right direction. Having a focus is also relevant for space, both because space for the index may be limited and in the sense that a succinct array is easier to scan. 

This also comes back to framing. What is the most effective frame for readers to recognize what they are seeking? As mentioned, often a single frame is sufficient, focusing on whatever is most relevant. In other instances, it may be better to include multiple frames if they hold equal weight. Either way, test the subheading(s) against the larger story or point that the book is making about that topic. 

Repeating locators within an array, across two or more subheadings, is usually a question of how that information is being framed. It is often best to avoid duplication, to avoid similar, parallel subheadings or an array that is too long. In other instances, in which discussions are complicated with intertwined subjects and themes, parallel subheadings may be justified. It is a matter of seeing the whole story that needs to be conveyed, and then deciding the best way to point readers towards that story. As with so much when indexing, it is less a question of right or wrong, and more a matter of weighing the relative merits and applicability of different approaches.

It is a big book, and it is taking a while to get through. It is also not the only large volume I’ve indexed this year. I feel like I’ve done more than usual, including an Oxford handbook on Baptist studies, an edited collection on Black Canadian art and literature, and a biography of Canadian poet Margaret Avison. These are books that are the equivalent of two or three regular-length volumes. 

Large books can be challenging to index. I have a theory that the length of the index grows exponentially with the length of the book (while, maybe not quite exponentially, but the length does grow), because the longer the book, the more details there are to index, the more locators there are, and the more likely subheadings are needed. Subheadings take up more space and take more time to write and edit, and so the work goes on and on. Also, the larger the book, the more there is to keep in mind. I need to remind myself to reset my expectations for how long the index will take. 

I still want to complete the index efficiently and as quickly as possible, even if the overall number of days and weeks is longer. I’ve been reflecting on what it is I do that is different compared to indexing a shorter book. This is what I’ve gathered so far:

• I write more notes for myself, such as brief summaries for each chapter. Because there is so much more to remember, I don’t want to forget what the beginning of the book was about by the time I reach the end. These notes can also help me see the overarching storyline and themes running through the book.
• I slow down and consciously remind myself to connect back to the big picture. With so many pages to get through, the temptation is to rush and to focus on picking up the easy entries—the low-hanging fruit—of people, places, reactors, chemical elements, etc…Those details are important and need to be picked up, but why are they important? What is the larger discussion or story? I need to make sure that I am creating headings and subheadings at those broader levels too, which means slowing down and understanding what all this is actually about.
• I write subheadings at a broader level. I still pick up plenty of smaller details, but I think broader subheadings are both easier to understand and navigate, and can help keep the array at a manageable length. For main characters and topics, which are going to have a lot of subheadings anyway, indexing less granular may be the difference between forty subheadings versus sixty or eighty, for example. Forty subheadings is still a lot, while still being easier to scan. 
• As I mentioned, broader subheadings can also be easier to navigate. This is because they encompass more and clearly express the larger context. Say a person is involved in constructing the National Research Experimental (NRX) reactor, is quoted reflecting on the reactor, and is also present for the reactor’s meltdown. A more granular approach would be to have separate subheadings for each of those three elements, which are arguably distinct. But in a large array, those three subheadings may sort apart from each other and a reader may not see all of them. Three distinct subheadings also take up more space (see point above). Better, I think, for a single subheading at a broader level, “National Research Experimental (NRX) reactor and,” to capture all of those discussions. The details of construction and meltdown can still be delineated as subheadings under the reactor itself. 
• While indexing at a broader level, I still want main headings and subheadings to be clear and specific. Indexing at a less granular level is not synonymous with being vague. If I go back, say when editing the index, and I don’t know what the subheading is referring to, then I can’t expect the reader to know. The meaning needs to be clear. Which reactor? Which relationship? Which concept or discovery? I try to make my first pass as clear as possible, so I have less work on my second pass and so I don’t leave myself confused when I come back around again.
• Lastly, I want to acknowledge that I use subcontractors on this large projects. I usually ask subcontractors to pick up the names of people, and perhaps also other common elements, such as, for the Avison biography, titles of poems and other works. Having a subcontractor handle these aspects frees up my headspace to focus on the subject entries and the overall structure of the index. It also helps me to get through my own draft more quickly, because I have less to pick up. So many thanks to the indexers I work with. With so much material to get through, I find it can make a noticeable difference.

In one sense, indexing a large book is no different from indexing any other book. I still pick up the same types of entries and my process doesn’t change too much. On the other hand, everything that makes indexing a regular monograph difficult is magnified simply because there is more of it. There are more details, more entries, more subheadings, more cross-references. I find writing the index requires a bit more planning, more notes, and more patience. Because the big picture is so big, it can be difficult to focus on, and so I need to make an even more conscious effort to keep referring back to what the book is about.

The big picture—the story that is being told—is the underlying aboutness, which needs to be visible in the index. I don’t want to get lost while indexing, and I don’t want the reader to be lost either. I need to slow down, think through my decisions, make sure I am seeing as clearer as I can in that moment, so that the reader can hopefully see through me.

The fundamental purpose of an index is to guide readers to the relevant information that the reader is searching for. To do that, the index needs to be clearly written, which begins with the first words that the reader sees. 

Main Headings

The main heading, also known simply as the heading, kicks off the entry. This is the first word or phrase that you see in an entry and array. It is typically a noun, and should be clear and concise. If a longer phrase is needed, the main heading should lead with the most important element. The main heading should also match how the term is used in the text, such as using the same spelling and capitalization. 

The heading should be reflective of both the text and the audience. Is the book discussing cars more generally or electric vehicles specifically? Or both? Will readers be reading this book to learn about the auto industry, new innovations, or specific brands and models? Or all of the above? To give another example, biblical characters such as Matthew, Silas, and Timothy probably don’t need a gloss clarifying their identity in a work of biblical studies to clarify their identities, but these names may be more unfamiliar to readers if they appear in other disciplines. 

Another consideration is whether or not to pluralize main headings. Should it be dog or dogs? Cantaloupe or cantaloupes? To start, be mindful of differences in nuance. Freedom is somewhat different from freedoms, for example. Otherwise, I tend to follow common usage. If a term is commonly pluralized, then I go ahead and make it plural in the index, which I think reads more naturally. 

To give a few examples of main headings:

Acts (biblical book)

Cleveland, Grover

electric vehicles

heat transfer

London (ON)

trade wars, retaliatory

Subheadings

For short arrays containing a handful of locators, a main heading is usually sufficient to specify what this thing is. But more specificity is often needed for topics with extensive discussion (usually when there are more than 6-10 locators) or if there are different aspects that readers would appreciate differentiated.

The subheading is placed after the main heading. Its purpose is to further clarify what this thing is. Because subheadings often differentiate references from one another, there are usually multiple subheadings per array.

Since the subheading is appended, there is more flexibility in how it can be phrased. Depending on the context, the subheading can be either a short word or phrase, or it can be longer and more descriptive.  In all cases, the relationship between the main heading and subheading should be clear. If possible, I try to also lead with the key word, which both affects how the subheadings are alphabetically sorted and, I think, makes it easier for readers to find the subheading as they scan the array. 

For example,

Acts (biblical book): authorship; within biblical canon; commentaries on; Paul within

Cleveland, Grover: first presidency; free-silver issue; legislative achievements; private life between presidential terms; second presidency

heat transfer: conduction; convection

Effective headings and subheadings connect readers to the text. Main headings are the point at which readers encounter the index, and readers should not need to guess what this thing is. The same is true for subheadings, if the reader decides to read further into the array. 

Tell the reader what they need to know. Be specific and concise. Do this, and your index will be well on its way to being excellent.

Is it primarily a process of extracting terms from the text? I’ve noticed, when talking to readers and editors, that this seems to be how many people conceptualize writing an index. It is less writing and more data mining. 

I want to suggest an alternative approach. While identifying and picking up key words is important, I don’t think that that is enough. A excellent index should also contain an element of storytelling. 

I also want to address a mistake that I’ve seen newer indexers make. It is being so focused on the myriad details of the text that they—and the index—lose sight of the larger context. I’ve noticed this especially in subheadings. I don’t think that this is an intentional mistake. Books contain such a tsunami of information that it can be difficult to know where to focus. This is why I prefer to spread the work out over several days, so my mind has time to process and absorb what I’ve read. If you struggle to keep the big picture in mind while indexing, I hope this reflection gives you some pointers.

As a caveat, while writing this I have in mind narrative-driven books. Think histories and biographies. These are books that typically contain a lot of detail while also telling a story. Other sorts of books, such as in the social sciences, how-to guides, or law, are more technical in nature and may not have an overt narrative (though every book should have some sort of structure). But even for more technical books, it is important to keep the larger context in mind. 

Context, Context, Context

In my book, Book Indexing: A Step-by-Step Guide, I discuss what I call the hierarchy of information. At the top is the metatopic, which is what the entire book is about. Below that are the supermain discussions, which are the handful of major arguments or areas of focus that comprise the metatopic. Below the supermain discussions are the regular discussions, which are the sub-discussions which flesh out the supermains. At the very bottom are all the little details, typically names, places, events, etc… All of these layers are nested together and should be reflected in the index.

When I refer to the context or the big picture of a book, I am talking about the metatopic, supermain, and regular discussions. These are the overarching discussions that give meaning to the smaller details. Problems can arise when the indexer fails to link back to the context, leaving readers confused about the meaning or relevance of an array or subheading.

Audience as Context

Before I jump into some examples at the subheading level, which is where I usually see this issue, I also want to mention that the book’s audience is also an important context. Not every detail is indexable. Before starting the index, think about what is important to the readers.

I’ve seen it happen when the indexer is so focused on picking up the details that they forget to assess whether the details are relevant. For example (and this is a made-up example, as I don’t want to embarrass anyone), say the book is a memoir on hiking Mount Everest. The author also briefly discusses, over a few paragraphs, a previous trip hiking Mount Kilimanjaro. Since it is discussed, Mount Kilimanjaro should have a main entry, but because the overall focus of the book—and presumably of readers—is on Mount Everest, the indexer does not need to pick up specific details about people and places associated with Mount Kilimanjaro. Those details are not relevant and will bloat the index. Instead, focus the index on Mount Everest. 

Using Subheadings to Tell a Story

Now let’s discuss subheadings.

Subheadings are crucial for breaking down large arrays into searchable chunks, but they are only effective if they are clearly written. Subheadings which are too granular and disconnected from their context are not helpful.

Consider this example. This is also made-up and is similar to real arrays that I have seen.  

Obama, Barack: communications with; congressional leaders and; economy and; Iraq and; oil and; as president; Senate and

How much do you understand about Obama from these subheadings? Do you have a clear sense of what you will find if you let these subheadings direct you?

To start, who is Obama communicating with? About what? It could be about anything. The subheadings “congressional leaders and’ and “Senate and” are a little more specific. If the text itself is vague or if these subheadings cover multiple interactions, then this level of vagueness may be appropriate. But what if we learn that these three subheadings are all referring to negotiations over the Affordable Care Act? Now we have context.

“As president” is also an unhelpful subheading, since most readers should know that Obama was president. Does it help to learn that the context is being elected during the 2008 presidential election? The other subheadings, for the economy, Iraq, and oil, may be clear enough, though it again depends on what the text is actually about. 

While all of these subheadings are technically correct—Obama is indeed communicating with someone, he is president, and he is doing something in regards to the economy—these subheadings also feel disconnected from anything concrete, at least to me. If we revise these subheadings to more accurately reflect the larger discussions, we get the following array. Which seems more connected to his presidency? Which is more helpful to readers?

Obama, Barack: 2008 presidential election; Affordable Care Act; economic policies; Keystone XL pipeline; withdrawal from Iraq

Let’s look at another example. Sometimes subheadings within an array are treated as a list, as in a list of names. 

Microsoft: Allen; Ballmer; Gates; Nadella; Wallace

These are all key players in Microsoft’s history. They are important and should all have main entries, but is listing them as subheadings really the best use of the Microsoft array? It doesn’t tell us much except that these people all have links to Microsoft. Why not use the subheadings to instead tell Microsoft’s story? Gates, Ballmer, and the others can still be in the index; just not the focus here. 

Rewriting the Book in the Index?

At this point, I can imagine a couple of objections. Is storytelling really appropriate within an index?

A common rule of thumb is to not rewrite the book in the index. I understand the point, that the index is supposed to direct readers to where the discussion actually is. But the index can only direct if the entries are clearly written. One of the best ways to be clear, in my opinion, is to connect to the larger context. I enjoy stories, and so I like to think of this as storytelling. If it helps, think of this as being clear and specific. What will resonate with the reader? Use that to hook the reader and send them in the right direction. 

It is also important to select the level of specificity that matches the discussion in the text. Returning to the Obama example, the Affordable Care Act is much more specific, and therefore more meaningful, than a generic subheading for healthcare policies. But if the discussion in the book is more like a broad overview, as in an overview of various economic policies, then a subheading at a broader level, like “economic policies,” would be the better choice.

Storytelling vs. Lists

I am also not saying that you should never make a list. Using subheadings to gather information into a list is also a valid approach. The two approaches can even be used in the same index. For example, for a book about Margaret Atwood, the main array for Atwood could tell the story of her life and career while a separate array—perhaps appended using the em-dash-modified format—could list all mentions of her novels and other writings. Books that are more technical in nature, rather than narrative-driven, may also favor lists over storytelling. The trick is knowing when each strategy is appropriate.

I also think that storytelling—making sure that the big picture is adequately represented in the index—can be more difficult to do, or at least more difficult to remember. It is summarizing and pointing towards the narrative and structure that exists within the book. Gathering together a list is often easier. 

When indexing, remember that you have options for how to present entries and information to the reader, and that your goal is to clearly communicate what the book is about.

Taking a Step Back

So how do you see the big picture? How do you channel that wave of information that is threatening to overwhelm you?

I find it helps to pause and take a step back. I especially do this if I feel like I’ve lost sight of the author’s argument or point. Or if there are a lot of names and other details and so it is easier to make two passes over that section, once for the details and a second time to see the full picture. I ask myself, “What is this discussion about, anyway?” Once I’ve identified the overarching discussion, I may need to go back and create entries for the context that I’ve missed.

If you struggle to see the big picture or the hierarchy of information, try to develop a habit of pausing and reflecting. Read until you hit a transition. Pause. How would you summarize the discussion you just read? How does the discussion fit into the larger structure or narrative of the book? Try completing the following sentence: “This section is about…” Be clear, specific, and meaningful. Once you have your answer, put it in the index.

So, assuming you understand the basic elements and process for writing an index, and you have received the page proofs from the client and are getting ready to start the index, how can you go about making a plan? 

For me, making a plan can be broken down into answering the following six questions.

1. What is the book about? This question is about determining the focus and scope of the book. I read the book’s description on the publisher’s website, if available. I also read the table of contents, and maybe skim the introduction and a couple of chapters. I want to get a feel for the main topics and headings that I will be picking up. With this broad sense of the book in mind, I may also begin thinking about how to translate that into the index’s structure.
2. Who is the audience? Beyond what the book is about, each index should be tailored to its audience. Will readers prefer a detailed index or a lighter index? Are readers picking up this book to answer a specific question or for entertainment? What does the audience already know about this topic, and what will they expect to find? Similar to determining what the book is about, considering the audience is also about focus and scope. Which details are relevant, and which irrelevant? Depending on the audience, not all details need to be picked up.
3. How much space is available for the index? This is a question to confirm with the client. If I can have all the space that I want, then space isn’t a factor in my decision-making. If there is a strict page or line limit, then I may need to make decisions about structure or which entries to include or exclude in order to fit. Planning ahead, I may consider using fewer subheadings, for example, or to outright exclude certain categories of details to ensure that the priority entries make the cut.
4. Does the book contain any specific indexing challenges? For example, are there a lot of illustrations? Are there legal cases that require special formatting? Are there terms from another language that contain diacritics or other special characters? Are there a host of family members that may need differentiating? It is not always possible to anticipate challenges, but if you can, now is a good time to consider your approach so you don’t get hung up partway through the index.
5. What is the publisher’s preferred style? If you are not familiar with the publisher’s style guide, now is a good time to review. I find it helpful to get the format right from the start, such as alphabetization and locator abbreviations, so I don’t have to think about it later.
6. What is my schedule? This is partly a question of the deadline to submit the index to the client, as well as a question of my own plan. Which days am I going to work on the index? How much am I aiming to complete each day? When do I want to finish the rough draft and when do I want to finish the final edit? 

All of these plans are, of course, contingent. It may take me longer than I expect to write the rough draft. I may discover an unexpected challenge. I may need to rethink my approach in order to keep the index short enough. Continuing to revise and refine the plan is, for better or worse, part of my indexing process.

But I find there are still benefits to thinking through all of these questions before starting. Knowing what the book is about and who the audience is helps to shape the entries I create and cuts down on irrelevant ones. The rough draft is usually a little cleaner and easier to edit. Indexing to the space available helps to avoid needing to make deep and painful cuts late in the process. Identifying challenges early means indexing correctly from the start, rather than going back to fix. Creating a schedule helps to keep me on track.

How much time should you spend making a plan? That is up to you. For many books, I only need about five or ten minutes to assess and make a plan. I may jot down a couple of notes and otherwise will keep my thoughts in my head. I’ve so far indexed around 500 books and many books are similar enough in terms of structure and genre conventions that I quickly know what to expect. Though I also work on some books that are more complicated or unique, and for those I do spend time digging into what it is I am unsure about. I am also aware of some indexers who use a checklist or form to help them prepare for each index. Find a system that works for you.

Writing an index is a constant process of decision-making. Making a plan can help streamline some of that decision-making, and provide confidence that you are setting out on the right path.