dependant datalists so that the selection of one item in the first list will limit the available items for selection in the second

Hi I have a general question, I was wondering if there is any way make a couple of dependant datalist so that the selection of one item in the first list will limit the available items for selection in the second? Is this possible with javascript alone. Thank you very much

Thank you for your response.

I should be more specific as to what I am trying to accomplish, I have a file that has on every line, a purchase order number, an associated estimate number, and an associated art-file number. These three numbers are not specific to each other and can be associated to other purchase order numbers, estimate numbers, and art-file numbers. I would like to have these numbers appear in three separate dependant list boxes so that typing in any of the fields would autocomplete the entry, and display in the other fields the associate numbers.

Each of these numbers could possible have multiple combinations to choose from. As the user makes their choice in each list box the number of available combinations narrows until they have the combination that they need.

I hope that I have explained this in a way that is understandable. Is using ajax the only way to accomplish this? Or is this possible using just html alone. Thank you again for your assistance