The 'Mail Merge' feature of Word is not powerful enough to do your mail out in a single pass since you have a number of complicating factors that go beyond the default functionality. But you can certainly do it via a series of passes. Or if you were an advanced user doing this mailout regularly then you could create and use a macro to do it with a single click.

To get started, you need to prepare the various contents of the mailout as separate mail merge docs for each 'Group'. Once the group's email is set up, filter the merge source to remove any rows which don't have that column marked and do the mailout to those rows. Do the same for the other groups.

This means you do three mailouts (one for each group) and just filter the dataset to align with the group you want to send to.

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Andrew Lockton
Chrysalis Design, Melbourne Australia