Role expressions enable one role to inherit the permissions of another role. This provides a flexible and convenient way of modifying existing roles or creating new roles. For example, suppose you want to create a new role named Team Leader, who needs similar permissions as a Data Modeler and an UML Modeler. Rather than manually adding each permission that those other roles possess, you can simply allow the Team Leader role to inherit the Data Modeler and UML Modeler roles. In this example, Data Modeler and the UML Modeler are role expressions of the Team Leader role.

To illustrate the example used above, the image below shows the role Expressions of the Data Modeler role. Selecting a role’s role expressions node displays, on the right pane, each of the other roles that has been added to the selected role. The properties of the Value column are Inherit or Disinherit, and they determine whether the permissions pertaining to the role Expression are added or subtracted from the aggregate permissions of the selected role. The Order column determines the sequence in which each of the role Expressions are processed. The Data Modeler shown here has the Macro Writer and UML Modeler role expressions.