The best way to do this is to use a Word style (say, Heading 1), and alter that style so that it page breaks before. The way you do this depends on the version of Word you're using. If you've got Word 2000 or 2003, there's an article all about using styles on my website:
http://www.alexhazel.me.uk. That same article is in the archive here, somewhere, but I can't remember where.
You basically need to find modify the style you're using for the chapter heading, go to the Paragraph settings, and look on the "Line and Page Breaks" tab. There, you'll find a checkbox labelled "Page break before". If you check that, Word will insert a page break before any paragraph that is of that style.
Alex
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modify...