Hi.  I am making a database to store interventions and student support services for students.  I think I need a one to many table so that I can identify the type of interventions (there are different reading and math programs) each student receives.  Some students will receive multiple interventions.  My question is:  Do I need an intervention ID like you have a parent one?  I wouldn't have a unique intervention for each student. I would imagine identifying either reading or math and then having the intervention type be the "many" part to the relationship.  I'm just not sure if I need a unique ID for that table.  Thanks for your help.