That amounts to a "multiple items per condition (=key field)" mailmerge
which Word does not really have the ability to do:
See the "Group Multiple items for a single condition" item on fellow MVP
Cindy Meister's website at
http://homepage.swissonline.ch/cindymeister/mergfaq1.htm#DBPic
Or take a look at the following Knowledge Base Article
http://support.microsoft.com/default.aspx?scid=kb;en-us;211303
or at:
http://cornell.veplan.net/article.aspx?&a=3815

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Hope this helps.
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Doug Robbins - Word MVP
>I have data in Excel in one row per outstanding invoice which includes
>client
[quoted text clipped - 6 lines]
> ie
> Just like a bank statement.