do you mean multiple licenses in the one office or more like poeple sharing the app with others in other businesses? if you are installing the app yourself you could always add in the mac address of the computers into a table and verify that when an app starts that the mac address is in the table.
Slán
~M

>I'm writing a new application and I'm considering the issue Multi-User Licenses.
>
>How can I ensure that only the specifies number of copies are being used and
>no more?