Developmental editing works with a manuscript as a whole to ensure the book idea is cohesive and executed well. It’s typically the first step in the editing process when an author hires a professional editor to help them revise their work. This order works well because changes after a developmental edit can often be substantial changes that directly affect future rounds of editing.
Nonfiction developmental editing is not done in the some way as fiction. During a developmental edit for nonfiction, I work with the following things: