>>>I have a form that contains 21 check boxes. Is there a simple, efficient way to determine which boxes are checked?
>>
>>You may create an array property for your form with all checkboxes listed. Then just navigate through this array and check status of each checkbox (Could be a second dimension in this array).
>
>Look at AMEMBERS() function to populate this array :-)

Right, though it could be even hardcoded for all these 21. If they have names like check1 - check21, you even don't need to an array (though I like this idea) and you can just do a simple loop...