That was the problem. Thanks.

I find it odd that in all the many web pages I read about this, I never encountered an explanation of precisely what constitutes the "exit" event. I am a complete neophyte - I never knew that pressing the tab key constituted exiting the formfield.

And many of the the people who use my document will never think to press the tab key once they make a selection. When one makes a selection in a drop-down list, one need not press the tab key to proceed to, for example, the next drop-down list - one can simply "mouse over".

So it would seem that I might be out of luck - there is no way that the users will be guaranteed to press the tab key to move on to the next field in the document.

That seems like an odd restriction - is perhaps something else I am missing?

Thanks again for your help.