Abstract: An order processing method for implementation in a distributed computer system is described. An order create request is received from a user at a local station, validated locally and routed to a remote station for authorization. Connection between local and remote stations may be of any type. Progress of an order is tracked by a configuration matrix, and communication is tracked and controlled by a router slip appended to an order message and which is in turn governed by the matrix. The matrix allows selection of a current control register which governs applicability of validation routines to data entities of the request or order. Paper handling is reduced or eliminated and sufficient control for decentralised purchasing is achieved.