I want to include a header that includes a variable page number, "P01, P02" etc.

See:  http://word.mvps.org/FAQs/Formatting/NumberingFrontMatter.htm

The link Greg gave you was not the most helpful one. You would have done (a little) better with http://WordFAQs.mvps.org/HeaderFooter.htm, though that article doesn't really focus on Word 2007/2010 but more on the theory of headers and footers.

Word 2010 does make it easier (in some ways) to create "great looking" (Microsoft's term) headers and footers, but much harder for some users to create a plain-vanilla header/footer from scratch. As you've discovered, the secret is just to access the header/footer directly and enter text the way you would in any other version. The alignment tabs are an advance over fixed tab stops, and the Header/Footer style does include these tab stops (Center and Right Margin) by default.

As Doug says, the easy way to insert a PAGE field is Alt+Shift+P (you can also use Insert | Page Number | Current Position). You can then add any static text you like (the P before the number). In this instance, because the Page Number Format dialog (Page Number | Format Page Numbers) does not offer the option of 01, 02, 03 numbering, you'll need to edit the PAGE field manually to achieve it.

1. Press Alt+F9 to display the PAGE field.
2. After PAGE, type # 00 so that the field looks like this:

{ PAGE # 00 } 3. Press Alt+F9 again and F9 to update if necessary.

Be aware that this page number formatting will not be reflected in the TOC, if any.

Greg Maxey's reply offers a link to a very good account of inserting headers/footers and page numbers. But it does not tell me how to include a variable page number AS PART OF MY HEADER. I do not want the page number to appear on a separate line from the header, but at the end of it. WordPerfect used to have some sort of symbol that stood for "number of the present page." I would like to include that sort of symbol in the header itself. Maybe it simply cannot be done in Word. I had to work around this problem -- fortunately in a rather short document -- by starting a new section on each page, then manually changing the page number in my header. My task was to duplicate/translate the header in a document I was translating, which is why I couldn't let the page number appear on a separate line from the header proper.

I have now found, in MS Word Help, the answer to my question. It is:

"Add a custom page number

1. Double-click in the header area or the footer area (near the top of the page or near the bottom of the page).

This opens the Design tab under Header & Footer Tools.

1. To place your page number in the center or on the right side of the page, do the following:
   • To place your page number in the center, click Insert Alignment Tab in the Position group of the Design tab, click Center, and then click OK.
   • To place your page number on the right side of the page, click Insert Alignment Tab in the Position group of the Design tab, click Right, and then click OK.
2. On the Insert tab, in the Text group, click Quick Parts, and then click Field.

1. In the Field names list, click Page, and then click OK.
2. To change the numbering format, click Page Number in the Header & Footer group, and then click Format Page Numbers.
3. To return to the body of your document, click Close Header and Footer on the Design tab (under Header & Footer Tools).

"

Greg Maxey's reply offers a link to a very good account of inserting headers/footers and page numbers. But it does not tell me how to include a variable page number AS PART OF MY HEADER. I do not want the page number to appear on a separate line from the header, but at the end of it. WordPerfect used to have some sort of symbol that stood for "number of the present page." I would like to include that sort of symbol in the header itself. Maybe it simply cannot be done in Word. I had to work around this problem -- fortunately in a rather short document -- by starting a new section on each page, then manually changing the page number in my header. My task was to duplicate/translate the header in a document I was translating, which is why I couldn't let the page number appear on a separate line from the header proper.