Conceptually, at least the way I'm used to thinking about documents ... a heading is something followed by a paragraph or other text object; if I'm working with a program that gives me an overview of document structure, I expect to see headings in that overview.

The Table of Contents is just another text object, generated on the basis of headings. If I'm working with a program that gives me an overview of document structure, all I expect to see is the heading "Table of contents". The entries in the table of contents are _not_ headings, because they are not themselves followed by text.



I've just been skyped by the colleague in question, and now we notice that while the Navigation (still) includes the ToC entries, it does not include the ToC Heading - so in terms of navigation, the Navigation pane is failing to show part of the document structure! All very strange ...

OK, so you are referring to the text formatted in the "TOC Heading" style. It does not show up in table of contents by default, as you have noticed. You can modify the style to include the desired outline level (in the Modify Style dialog box, click Format, Paragraph, and specify an "Outline level" on the Indents and Spacing tab). However, since tables of contents, by default, are based on outline levels, you would get a duplicate in the TOC of the text formatted in the "TOC Heading" style.

You could give the TOC Heading an outline level which would make it show up in the Navigation pane. However, if your TOC is based on outline levels (which is the default setting) you would see text formatted in the TOC Heading style in the TOC as well.

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Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional