Ian
You want to copy data from a field in one table into a field in another
table? Unless you are describing putting a "foreign key" value into the
second table, based on a primary key in the first, you really don't want to
do this! Not with a relational database like Access.
And if you are talking about a foreign key, the easiest way to do this is to
use a main form/sub-form approach. The sub-form "inherits" the primary key
value from the table behind the main form, and treats it as a foreign key.
Good luck
Jeff Boyce
<Access MVP>