Use an If...then...Else... field
{ IF { MERGEFIELD Address2 } <> "" ", { MERGEFIELD Address2 }" "" }
You must use Ctrl+F9 to insert each pair of field delimiters. Put this
field construction immediately after your Address1 mergefield and note that
there is a space after the comma.

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Hope this helps.
Please reply to the newsgroup unless you wish to avail yourself of my
services on a paid consulting basis.
Doug Robbins - Word MVP
> Is there any way to display punctuation after a merge field depending on
> whether or not there is any data in that field? For instance, I have a
> sentence that includes an Address1 field and an Address 2 field. I have a
> comma between the two address fields. If some of the records that merge do
> not contain a second address, I don't need the comma that prints after the
> first address. Is this possible with Word 2003?