In a method for providing differential access to a digital document among workflow participants, in which at least one of the workflow participants is outside of a common secure environment (300), a first set of keys including an encryption key, a signature key, and a verification key is associated with atomic unit(s) (304). The atomic unit(s) is encrypted using the encryption key and signed using the signature key (306, 308). A level of access to the atomic unit(s) to be granted to each of the workflow participants and the keys in the first set of keys to supply to each of the workflow participants based upon the identified level of access are identified (310, 312). In addition, each of the workflow participants is supplied with the identified one or more keys (314) and the encrypted and signed atomic unit(s) is supplied to a first workflow participant (316).