This is not difficult: but you need two fields, one for the YearNumber and
one for the SerialNumber. You also need a way of allocating the
SerialNumber -- access/ jet cannot do this automatically so you will have
to program it into your form(s) and make sure that nobody can insert new
records without going through your data entry forms.

Try googling for Access Custom Autonumbers, or else look at Dev's Access
site on <http://www.mvps.org/access> for details on the code required.

No: you need a single Primary Key consisting both the YearNumber and
SerialNumber fields. You can display your number by concatenating them on a
form or a report like this:
 
 = Format(YearNumber,"0000") & "/" & Format(SerialNumber,"000")

Hope that helps

Tim F

This is called an "Intelligent Key" in the trade - and that's not a
compliment. Storing two pieces of data in one field is *emphatically*
a Bad Idea.

I would suggest using two fields, BookingYear and BookingSeq. You can
ctrl-click both fields in table design view and make them a joint
Primary Key. The Default property of BookingYear could be

Year(Date())

to set it to the current year. To get BookingSeq you must - no option,
tables don't have any usable events - use a Form to do your data
entry. You can put VBA code in the Form's BeforeInsert event such as:

Private Sub Form_BeforeInsert(Cancel as Integer)
Me!BookingSeq = NZ(DMax("[BookingSeq]", "[your-table]", _
  "[BookingYear] = " & Year(Date()))) + 1
End Sub

                 John W. Vinson[MVP]