>>I would put no code in Valid, and look at using Click.
>>In Click:
>>
>>This.Lostfocus
>>
>>to fire whatever code you have in your Lostfocus. Will that work?
>
>Won't the Click fire every time the user clicks on the box, even if it's not dropped down?

What kind of box is it? There are two ideas in play here:

1) The Click does not fire when user clicks on the "dropdown arrow" - so a normal selection can be made without any problems.
2) Any other behavior (incremental search, e.g.) can be controlled in the Lostfocus by stopping exit with a NoDefault. I don't know the details of what you're doing, but the hope is that a combination of these two ideas will help...