Milan,

One way to do it is to use an unbound form for data entry, and some
simple VBA code to write the record to the table at the click of a
button (Save); you can use either a recordset operation or an append
query to save the new record, and look up the last used PK value (DMax)
right before the record save. This all happens so fast that the chances
of two new records colliding (two users clicking the button on the same
split second) are next to nothing.

HTH,
Nikos