1. A method for supporting transactions of property between ones of a defined group of users, each with a user identifier, comprising: providing a registry comprising a database of electronic records stored in a memory of a computer system in which each record represents a bill of lading supporting one transaction of property between the defined group of users and wherein each record comprises a plurality of role fields, wherein at least one role field reflects the rights and obligations of users named in the role field relative to property underlying the transaction; indicating, in at least one role field of the record, a user identifier of a user that has an exclusive ability to modify the record; receiving, at the computer system, an electronic message from a transmitting user, wherein the message comprises a user identifier of the transmitting user and a registry instruction to change the user identified in at least one role field to reflect a change of the user that has the exclusive ability to modify the record; automatically validating the transmitting user identified in the electronic message, with the computer system, by comparing the user identifier in the received electronic message to the user indicated in the record as having exclusive ability to modify the record; automatically validating the registry instruction in the electronic message, with the computer system, by determining if the registry instruction conforms to a set of rules, the set of rules being predefined to reflect rules relating to the transfer of property, to which all users are bound to adhere by a common contractual agreement; automatically modifying the record to change the identity of the user that has the exclusive ability to modify the record, with the computer system, if the transmitting user is a valid user and the registry instruction is a valid registry instruction; preventing modification of the record if the user is not a valid user; and preventing modification of the record if the registry instruction is not a valid registry instruction.