Thanks Des,

If you look at the very first post my example showed both Country and continents as reference data in TableA and TableB (here I was trying to show how...

Many thanks for your help both,

I will have a go in an hour and see whether I can get it working.

One added bit of complexity (I don't think I explained...

Ha,  ok I am sorry.  I was trying to explain the best way I could.  Many thanks for the advice,  I will do it that way in future.

Mike