Just use an envelope type mailmerge with the appropriate mergefields from
the data source in the return address area of the envelope and type your
address into the address area.

Signature
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Hope this helps,
Doug Robbins - Word MVP
> We include self-addressed return envelopes in our mailings, so the
> addressee
> is the same, but we would like to have the original addressee's name and
> address as the return address on the self-addressed return envelopes. Any
> suggestions?