I don't know where my reply to this went to. I have looked at that page and used them on several sites, but it doesn't explain how to have Parent 1 + Parent 2 decide what options in the child list are available. Since I didn't get a help response I went ahead and created a 4th table that allows a type of hardware to be chosen and it shows a list of type/manufacturer combinations that are available, but this means maintaining another table and as those combinations expand I need to add them to that table. I was hoping to avoid maintaining another table as that will be an easy one to miss so people can't enter the correct data until it's added there first.