You can execute a Word mail merge from within Access using automation, but I
think what you might have in mind is generating an Access report rather than
mail merging per se, i.e. not using Word at all.  This is a lot simpler; its
simply a case of designing a report, e.g. a pro forma letter, based on an
Access query, forcing a new page after the report's detail section so that
each record is a separate page in the report.

You can control the process from an unbound dialogue form with, for
instance, a list box in which you select which report (the equivalent in this
situation to a Word template) to open and other controls on the form in which
you enter or select parameters for the report, which will govern which
records are printed.  As you'll probably need different parameters for each
report you can hide/show the relevant controls for the one selected by some
code in the list box's AfterUpdate event procedure.

The selected report would be opened from a button on the form, or two
buttons, one for previewing, one for printing.

The query underlying each report would reference the controls on the form as
parameters.

An Access report would not give you as much control over the formatting as a
Word document does, but for most purposes is perfectly good  Take a look at
the Invoice report in the sample Northwind database which comes with Access
to see the sort of thing which can be done.  In the application this is
normally printed for just one invoice form the Orders form, but there is no
reason why it could not equally well be printed for multiple invoices.

Ken Sheridan
Stafford, England

You should also take a look at Albert Kallal's Super easy Mail Merge

http://www.members.shaw.ca/AlbertKallal/msaccess/msaccess.html