Sabine, have a look here,

http://www.mcgimpsey.com/excel/udfs/sequentialnums.html
--
Paul B
Always backup your data before trying something new
Please post any response to the newsgroups so others can benefit from it
Feedback on answers is always appreciated!
Using Excel 2002 & 2003


"Sabine" wrote in message
...
We are currently using a manual shipping form each time we want to ship
something and the shipping department manually processes it and returns a
carbon copy of the form.
We'd like to automate that in Excel (not sure if Outlook would be better)
but need to be able to assign a consecutive number that can be referenced
by
the shipping department. This would mean that each time, a user accesses
the
form, a new number needs to be assigned to the form. Sometimes a user
might
use the form 20 times a day.
Thanks so much for your help.
Sabine