As simple as ABC?

Alphabet letters A, B and C

We know the order of the 26 letters, so it should be straightforward to apply this to a list of words, shouldn’t it?

Look at these lists. Which one do you think is correct?

List AList B
class actionclass action
class warclassicism
classroomsclass war

Did you think List A is correctly ordered? You’re right.

Don’t worry if you thought it was List B. You’re also right. But how?

These two lists are examples of two different systems that treat the spaces and punctuation between words differently.

List A is in word-by-word alphabetical order. In this system the spaces and hyphens between words are given filing value and they should be arranged before any other letters. This means all the terms which have a space or hyphen after ‘class’ should come before longer single words such as ‘classes’.

List B is in letter-by-letter alphabetical order. In this system the spaces and hyphens are ignored and only the letters have filing value. This means that ‘class war’ comes after ‘classrooms’.

It gets even more complicated than that; some systems vary on how they treat hyphens adding a whole new set of variations. Have a look at List A and List C below.

List AList C
class actionclass action
class-leaderclass war
class warclasses

List A is in the International Standards Organization version of word-by-word alphabetical order. The hyphens are treated as having the same value as spaces, so class-leader is higher up the list.

List C is the Chicago Manual of Style version of word-by-word alphabetical order. The hyphen is treated as if it were not there, treating ‘class-leader’ as ‘classleader’ and filing it between ‘classics’ and ‘classrooms’.


Professional indexers use specialist indexing software with different settings to create the sort order required by the project they are working on. Different publishers will have preferences according to their house styles.


Don’t miss finding the item you are looking for when you are using an index. In complex indexes there will often be a note at the beginning explaining which type of alphabetical order is being used.


Are you intending to index your own book? Be aware of the different types of alphabetical order. Maybe consider hiring a professional indexer to help you.

Indexing Students

Always double-check your alphabetical order and remember that there are different forms of word-by-word order. Check your software settings.


Remember that professionally trained indexers have the software tools and knowledge to create the best quality indexes.