A method of configuring quality of service for a return path of a bi-directional label switched path within a network, the bi-directional label switched path having a forward path and the return path, the method comprising the steps of: configuring a label information context (72, 156) for a quality of service configuration of the return path of the bi-directional label switched path separate from a quality of service configuration for the forward path; forming a path set up message (46, 48, 50) containing a return path quality of service object indicating the quality of service configuration for the return path separately from the quality of service configuration for the forward path; and sending the path set up message (46, 48, 50) containing the return path quality of service object to a network node (14, 16, 18) in the bi-directional label switched path, wherein the path set up message (46, 48, 50) enables a plurality of quality of service classes to be supported by the bi-directional label switched path, and wherein the return path quality of service object, included in the path set up message (46, 48, 50), comprises: at least one field indicating a number of one or more entries (134, 136) being included for each quality of service class to be supported by the bi-directional label switched path, each entry of the one or more entries (134, 136) comprising a reserved field, an experimental field, and a per hop behaviour identification; and the one or more entries (134, 136), each entry of the one or more entries (134, 136) defining a mapping, for the return path, between the experimental field and a per hop behaviour associated with the per hop behaviour identification, such that the quality of service configuration for the forward path is specified separately from the quality of service configuration for the return path. configuring a label information context (72, 156) for a quality of service configuration of the return path of the bi-directional label switched path separate from a quality of service configuration for the forward path; forming a path set up message (46, 48, 50) containing a return path quality of service object indicating the quality of service configuration for the return path separately from the quality of service configuration for the forward path; and sending the path set up message (46, 48, 50) containing the return path quality of service object to a network node (14, 16, 18) in the bi-directional label switched path, wherein the path set up message (46, 48, 50) enables a plurality of quality of service classes to be supported by the bi-directional label switched path, and wherein the return path quality of service object, included in the path set up message (46, 48, 50), comprises: at least one field indicating a number of one or more entries (134, 136) being included for each quality of service class to be supported by the bi-directional label switched path, each entry of the one or more entries (134, 136) comprising a reserved field, an experimental field, and a per hop behaviour identification; and the one or more entries (134, 136), each entry of the one or more entries (134, 136) defining a mapping, for the return path, between the experimental field and a per hop behaviour associated with the per hop behaviour identification, such that the quality of service configuration for the forward path is specified separately from the quality of service configuration for the return path. at least one field indicating a number of one or more entries (134, 136) being included for each quality of service class to be supported by the bi-directional label switched path, each entry of the one or more entries (134, 136) comprising a reserved field, an experimental field, and a per hop behaviour identification; and the one or more entries (134, 136), each entry of the one or more entries (134, 136) defining a mapping, for the return path, between the experimental field and a per hop behaviour associated with the per hop behaviour identification, such that the quality of service configuration for the forward path is specified separately from the quality of service configuration for the return path.