As the map to a book, an index goes beyond the brief overview of the table of contents and reveals subject matter in detail. Without the index, access to a book's information is severely compromised. If readers are unable to navigate their way around the text, the good work of an author can be undone.
Traditionally, indexes reflect the main part of the text and will not reference material found in front and back matter such as the foreward and appendices. However, author requests that entries from these sections be included in the index can be easily accommodated.
There are a variety of index types. Abbreviated indexes are produced when there are space limitations or for an audience of younger readers. Scholarly texts require a rich, detailed index with multiple subheadings. Indexes for textbooks include plenty of cross-references to aid readers who may be unfamiliar with the jargon of a subject. Readers of books created for workshops will look to an index for access to those areas of the text which emphasize action steps and tricks of the trade.
Accessibility of the index is key. The easiest index format to read is the indented style consisting of a main entry followed by a column of subheadings. However, due to space constraints or large texts, the run-in style - which formats the index in a paragraph rather than in a column - may be a better choice. Editors will often provide a house style sheet with particular indexing specifications.
While an index must reflect the text accurately, there are times when theological or philosophical material requires adjustments to attain that accuracy. With such books, it is best to set up a regular schedule with the client to review the index-in-progress and get real-time feedback on the most challenging sections.
Indexing rates vary depending upon the length of the text and the density of the material. Discounts are available for projects with extended deadlines.