FWIW, I never use that particular dialog. The TOC styles are all set to
automatically update, so any change you make to TOC entry formatting in the
TOC will update the style, and it's much easier to see what you want when
looking at the TOC itself than when staring at the Modify Style dialog (and
having to go to the Paragraph, Font, and other dialogs separately).

To answer your specific question, I'm not sure exactly what you mean. The
styles you are modifying are the TOC entry styles (TOC 1, TOC 2, etc.), and
yes, you are modifying them for the entire document. This can be tricky if
you have more than one TOC. What you can do if you need, say, TOC 1 to be
different in two different TOCs is to use *different* styles. There is no
law that says Heading 1 has to be represented by TOC 1, for example. In any
given TOC, you can type a 4 beside Heading 1 in the Options dialog, and
Heading 1 will use TOC 4, which you can format quite differently from TOC 1.
Once you understand this concept, you have much more latitude in setting up
a TOC the way you want it.

Just one example: Suppose you have a three-level TOC and you want to omit
numbering for levels 1 and 3 but show page numbers for level 2 (trust me on
this: sometimes this can actually happen). In the TOC field code, you can
use a switch to omit numbering for certain levels, but they have to be
contiguous: you can omit numbering for levels 1 and 2 or 2 and 3, but not 1
and 3. So you use TOC 2 for Heading 1 and TOC 1 for Heading 2 and omit
numbering for levels 2 and 3. Shazzam!

--
Suzanne S. Barnhill
Microsoft MVP (Word)
Words into Type
Fairhope, Alabama USA
Word MVP FAQ site: http://www.mvps.org/word

Take a look at How to Create a Template - Part 2 on the MVP FAQ page - and
download the Word version which contains the described template.
--
Charles Kenyon

Word New User FAQ & Web Directory:
<URL: http://www.addbalance.com/word/index.htm>

Intermediate User's Guide to Microsoft Word (supplemented version of
Microsoft's Legal Users' Guide)
<URL: http://www.addbalance.com/usersguide/index.htm>

Word Resources Page
<URL: http://www.addbalance.com/word/wordwebresources.htm>