You create IDEF3 scenario diagrams as a product of the operational rules model. The scenario diagram in IDEF3 Process Modeling is the top-level diagram process flow diagram for a part of a business or a system.
When you create a Scenario diagram, you must create a new Operational Rules Model diagram. You cannot designate an existing IDEF3 diagram as a Scenario diagram.
1 Create a new diagram of type NOV-6a Op. Rules Model.
2 In the IDEF3 Diagram properties dialog box, select Scenario Diagram.