Marc,
I've used SPServices successfully for a couple of projects. One recent struggle I'm hoping you can help with is similar (if not the same) as Phil's.
Example: Cascading Lookups for columns A through D. Column D's lookup needs to not only be based on the selection in column C, but that of A, B and C.
Is this the same issue where I should be using the ID as the key?
I appreciate any assistance. Thanks, Jack