Hi David

Don't use Master documents for this. There are all sorts of issues with them
(see
http://word.mvps.org/faqs/general/RecoverMasterDocs.htm for the full story)
and in any case if you are sending the document to other people you will
make things unnecessarily complicated.

Starting from existing subdocuments, you can either combine them into a
single document (using copy and paste, or Insert > File) or you could use
the {INCLUDETEXT} field (Insert > File using the Insert Link option) to
maintain them as separate files if that's convenient for other reasons. In
the latter case, before you send the file you may want to make a copy in
which the fields are unlinked (the text is locked in place) so you don't
have to grapple with sending multiple files and fighting pathnames.

No one can tell you how to make master documents work in word, because:

Why Master Documents corrupt
http://www.mvps.org/word/FAQs/General/WhyMasterDocsCorrupt.htm

How to recover a Master Document
http://www.mvps.org/word/FAQs/General/RecoverMasterDocs.htm

http://www.addbalance.com/word/masterdocuments.htm

General advice from the experts is that putting all chapters (if you have
chapters) in one document as different sections (not always necessary), and
using styles and headings properly, works fine for long documents.

DM