Policy: Transactions under $X can be raised and approved by the same person. >X requires an independent approver with permission “supervisor”. Activity: Alice

Policy: Transactions under $X can be raised and approved by the same person. >X requires an independent approver with permission “supervisor”. Activity: Alice (a supervisor), raises a transaction >X, Bob is a supervisor, Eve is not. Problem: “Who can approve the transaction?” (As humans the answer is obviously Bob, but for typical implementation approaches to AuthZ policy, this is challenging to determine. Typically it’s done out of band and then makes a decision when requested by Bob (allow) or Eve (deny))