An electronic commerce system facilitates secure electronic commerce transactions among multiple participants. Each electronic commerce transaction involves at least one commerce document defining the transaction and at least one commerce instrument defining a payment for the transaction. The electronic commerce system has a credential binding server at a trusted credential authority, multiple computing units at associated participants, and a communication system interconnecting the credential binding server and the multiple computing units. The electronic commerce system operates in two phases: a registration phase and a transaction phase. During the registration phase, each of the computing units generate and send a registration packet over the communication system to the credential binding server. Unique credentials are produced by the credential binding server based upon the registration packets sent back to the computing units. During the transaction phase, an originating computing unit initially requests, receives, and verifies the credentials of expected recipient computing units to ensure communication between authenticate participants. Thereafter, the originating computing unit signs and encrypts the commerce document(s) and the commerce instrument(s) in a manner which ensures that only the intended recipients can decrypt them. The originating computing unit then sends both the commerce document(s) and instrument(s) over the communication system to a first recipient computing unit. The first recipient computing unit decrypts and verifies the commerce document(s) and/or instruments intended for it. The first recipient computing unit then passes the balance of the encrypted commerce document(s) and/or instrument(s) over the communication system to a second recipient computing unit, which decrypts and verifies the commerce document(s) and/or instrument(s) intended for it. This process is continued until all commerce documents and commerce instruments are distributed, decrypted, and verified by their intended recipients.