Structural editing, line editing, copyediting and proofreading: what’s the difference?

Dr Denis Savelyev · October 2026 · 6 min read

Editors use these terms constantly, and not always consistently. Here is a plain-English guide to the stages of editing, where line editing fits, and which stage your thesis, article or book actually needs.

If you have ever asked an editor for “a proofread” and been told your manuscript really needs a copyedit, you are not alone. The vocabulary of editing is confusing, partly because different countries and sectors use the same words in slightly different ways. This guide sets out the stages as they are generally understood in Australian publishing, drawing on the Institute of Professional Editors’ Standards for editing practice, and notes where usage differs.

The key principle is that editing moves from the big picture to the fine detail. Each stage assumes the one before it is finished. There is no point perfecting the commas in a chapter that may later be cut in half.

1. Structural editing

Also called substantive or developmental editing, this looks at the manuscript as a whole. Does it have the right shape for its purpose and readers? Questions at this stage include:

• Is the material organised in the most logical order? Should sections be moved, merged or split?
• Is the argument developed and signposted clearly from introduction to conclusion?
• Are some parts too long and others underdeveloped? Is anything missing or repeated?
• Are the tone and level of explanation right for the intended readers?
• Are headings, tables, figures and appendices doing their job?

The result is usually an editorial report plus comments on the manuscript. The author then revises. A manuscript assessment is a lighter version: a read-through and written report, without detailed comments throughout.

For theses: structural editing is not appropriate. Under the IPEd Guidelines for editing theses, content, argument and structure are matters for the candidate and their supervisors. An editor may point out a structural problem but should not solve it.

2. Line editing

Line editing is where the terminology gets slippery. In US trade publishing, a line edit is a distinct stage that focuses on style: the rhythm of sentences, word choice, tone, transitions and the overall readability of the prose, paragraph by paragraph. It sits between structural editing and copyediting.

In Australia, line editing is usually treated as part of copyediting. Writers Victoria, for example, describes the stage as “copy (or line) editing”. In practice, the difference is one of degree. A light copyedit corrects and makes consistent; a heavy copyedit (or line edit) also smooths and tightens the prose.

In my academic editing, copyediting covers this sentence-level work on clarity and flow; I don’t offer line editing as a separate service. For theses, the line work is limited to clarity of expression. It never extends to rewriting in my own voice.

3. Copyediting

Copyediting is the core of most academic editing. The copyeditor works through the text line by line for accuracy, clarity and consistency:

• grammar, syntax, spelling and punctuation;
• clear expression, removing ambiguity, wordiness and needless repetition;
• correct and consistent terminology, abbreviations, transliterations and units;
• consistent capitalisation, hyphenation, numbers, italics and headings;
• citations checked against the reference list, both formatted to the required style;
• consistent presentation of tables, figures and captions.

A good copyeditor also keeps a style sheet, a record of every decision about spelling, terminology and style, so that chapter seven follows the same conventions as chapter one.

4. Proofreading

Proofreading is the final check, ideally done on the formatted or typeset version once everything else is finished. The proofreader looks for remaining typos and errors, but also checks that all parts are present and in order, cross-references and page numbers are correct, and the layout has no problems such as awkward page breaks. A proofread should involve only a few corrections per page. If it involves many more, the document probably needed a copyedit first.

Where does typesetting fit?

For a printed book, typesetting (laying out the pages) happens after copyediting and before the final proofread. Proofreading the typeset pages catches any errors introduced during layout, which is why it is worth doing even after a careful copyedit.

So which do I need?

• A thesis: copyediting, then a final proofread, within the IPEd Guidelines and with your supervisor’s approval.
• A journal article or chapter: usually a copyedit and a check against the journal’s guidelines; occasionally structural feedback if reviewers have asked for reorganisation.
• A scholarly or non-fiction book: often all of them: structural editing on the full draft, a copyedit once revisions are done, typesetting, then proofreading of the typeset pages.

If you are unsure, send a sample. Any experienced editor should be able to tell you, honestly, what level of editing your manuscript needs, and that may be less than you expect.

Want an honest assessment of your manuscript? Send me an enquiry with a few sample pages.