The Maille Authorization protocol provides flexible and reliable authorization in large distributed and pervasive computing systems. Service owners distribute their access control lists across the network using threshold cryptography. Instances of the distributed service need only verify that requestors have knowledge of a specific secret provided by the Maille Authorization system. Requestors use the Maille protocol to find and retrieve individual parts of the scattered key. Once a sufficient quorum of nodes holding the key is found, the requestor can reassemble the key and is authorized. Unlike extant systems, the Maille Authorization protocol has no single administrative point of failure and tolerates multiple simultaneous Byzantine failures.