Hehe I am just making it worse... Sorry You can test an array of UDTs for not being dimmed (which is what I thought you were doing in you example and what I showed in my own example). And the usual methods of bound-checking of does work (at least I haven't found a breaking scenario yet).

But what I was trying to say was I think the OP was less worried about checking the entire array, and seeing if a specific element in said array was not used. (As in vbNullString if it were a string array).

Since an empty UDT will look different for each individual UDT, the most flexible way (IMO) to see if element in a UDT array is empty is to just be able to compare it to an Empty Variable of the same user defined type. To do that you need to be able to perform a comparison of two UDTs (the element to be tested, and the empty UDT). If the tested element is equivalant at the byte level to an empty version of the UDT (which is what I posted earler will check) then the element is empty.

But as far as I have noticed an array of UDTs performs no different than any other array.

/Me hopes he has not made it worse by explaining