While many authors of nonfiction books or memoirs feel that a professional book editor would only change the tone and relevance of their work, it is actually quite important for all books to receive attention from an experienced editor. The factual nature and implicitly personal aspects of a nonfiction manuscript often makes receiving feedback, criticism, and corrections tough for an author. However, nonfiction editors with previous book experience will have many angles for reviewing the book. A professional nonfiction editor will consider issues such as voice, tone, character development, and organization.

When considering the voice an author has used in a manuscript, an editor will look at the way word choice and phrasing determines the emotional connections that a reader makes with the narrative. The editor will also review the author's style of sentence construction and pacing, both of which factor into an author's voice. Issues such as distance from the narrative, philosophical turns, and moral stance all play a key role in crafting a strong voice, and an editor is capable of providing guidance and assistance in these areas. As far as tone is concerned, authors may be more worried with conveying the events of their narrative with factual clarity and rigid attention to historical accuracies than with crafting a perspective on the events. An editor will be able to help an author ensure that their narrative takes on a viewpoint, or tone, which conveys their attitude towards the topic and characters.

Characterization is another area where an editor can offer guidance. As anyone who has written nonfiction manuscript can attest, it's tough to create round characters from people that are close to an author. Nonfiction editors will be able to offer unbiased suggestions about how characters have been developed and whether or not they meet the author's desired representations. There are also matters of libel that an editor can advise on such as whether or not an author's portrayal of an actual person might cross lines of good taste and fair representation. Lastly, an editor offers fresh pair of eyes that can help pare down any excessive descriptions or characteristics that might be possessed by a real person but which fail to provide value to a written narrative.

Organization, or plot structure, can be tricky with any narrative but even more so with a nonfiction book. An author's first inclination in a nonfiction title is often to tell the narrative in a direct, linear manner that simply goes from the beginning of the action to the end of the action. Many authors refrain from jumping around in the chronology of the plot, despite the fact that it often will create more tension, drama, and emotional impact for a reader. An editor's goal will be to clarify the plot points and help an author arrange them for the greatest effect. So, even if an author thinks they don't require an editor, hiring one would surely enhance the quality and the clarity of the content.