In my opinion the use of UDTs carry little advantage. If you refer to Peter's example all the way back on page 1 about using a UDT to hold an entire "object" like a bill, it begs the question of why you are even working with a RDBMS in the first place. "Old Fashioned" row??? Regardless of how long the RDBMS has been around, it isn't being improved by this "fake" normalization. There is no better way to store information in a RDBMS than using a main table and one of several possible "lookup" table designs for the detail records. That's what this is all about.