I am trying to figure out how to design a database that has items that contain other items (a basic kit or BOM). In that, I need to be able to reference the item description of the child items in the parent item. A further complication is that each item is associated with an item category. Each item category has unique fields that when concatenated represent the item description. I have no idea how to diagram this. Ex. Item Name Item Description Qty Item Category Item1 Double 3-0 x 7-0 1 1/4 SC Primed 7 1/4 FJP Jamb 1 Finished Wood Door Item2 3-0 x 7-0 1 1/4 SC Primed 1 Door Leaf Item3 7 1/4 FJP Jamb 1 Jamb In terms of Quanitities Item1 takes 2 of Item2 and 3 of Item3. Item1 takes the concatenation of Item2's description (category Door Leaf first followed by item category Jamb) Item Category Door Leaf requires a number of fields that are concatenated into the item description they are: Door Type : Double, Single, Pocket, Bypass, Bi-fold Width: 3-0 (three feet 0 inches) Height: 7-0 Thickness: 1 1/4 Door Core: SC Door Finish: Primed Item Category Jamb requires a number of fields that are concatenated into the item description are: Jamb Thickness: 7 1/4 Jamb Material: FJP There are more characteristics for each of the Item Categories, but I only selected a few for purposes of example In order to design this properly, I need to know what tables I need, and what the primary and foreign keys are? I'm kinda stumped. Thanks, Marc --Disclaimer--Chinook Materials-- This message (including any attachments) is intended only for the use of the individual or entity to which it is addressed and may contain information that is non- public, proprietary, privileged, confidential, and exempt from disclosure under applicable law. If you are not the intended recipient, you are hereby notified that any use, distribution, or copying of this communication is strictly prohibited. Although steps have been taken to check for viruses, the recipient(s) should also check to ensure messages are virus free.