That indeed does the trick, thanks.
Just one thing, if i do that then i can use drop down list however I cannot use 'Auto complete using value list'.
Do you know of a way around that?
Auto-complete can't be used when an ID number is the first value list field. Here's a way around that:
FileMaker 12 users: https://dl.dropbox.com/u/78737945/SimpleNameLookupDemo.fmp12
Pre FileMaker 12 Users: https://dl.dropbox.com/u/78737945/SimpleNameLookupDemo.fp7